Air conditioner

Abstract

The invention discloses an air conditioner. The air conditioner comprises an indoor heat exchanger, an outdoor heat exchanger, a compressor, a concentration sensor and a controller. The compressor is configured to compress a gaseous refrigerant. The concentration sensor is arranged indoors and is configured to detect the current concentration value of a refrigerant in the indoor environment. The controller is configured to control the air conditioner to operate in a first recovery mode when the current concentration value, detected by the concentration sensor, of the refrigerant is larger than or equal to a preset first leakage concentration value and the indoor heat exchanger works as an evaporator; and when the current concentration value, detected by the concentration sensor, of the refrigerant is larger than or equal to a preset first leakage concentration value, and the indoor heat exchanger works as a condenser, the air conditioner is controlled to operate in a second recovery mode.

Description

air conditioner

[0001] This application claims priority to Chinese patent application No. 202210763742.4 filed on June 30, 2022, and priority to Chinese patent application No. 202210763748.1 filed on June 30, 2022, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present disclosure relates to the technical field of household appliances, and in particular to an air conditioner. Background Art

[0003] An air conditioner's refrigeration cycle uses a compressor, condenser, expansion valve, and evaporator. This cycle involves a series of processes: compression, condensation, expansion, and evaporation. The air conditioner's refrigeration cycle relies on the refrigerant, which releases heat during condensation and absorbs heat during evaporation, thus enabling heat exchange and transfer.

[0004] Summary of the Invention

[0005] In one aspect, an air conditioner is provided. The air conditioner includes an indoor heat exchanger, an outdoor heat exchanger, a compressor, a concentration sensor, and a controller. The compressor is configured to compress a gaseous refrigerant. The concentration sensor is disposed indoors and is configured to detect a current concentration value of the refrigerant in the indoor environment. The controller is configured to control the air conditioner to operate in a first recovery mode when the current concentration value of the refrigerant detected by the concentration sensor is greater than or equal to a preset first leakage concentration value and the indoor heat exchanger operates as an evaporator; and to control the air conditioner to operate in a second recovery mode when the current concentration value of the refrigerant detected by the concentration sensor is greater than or equal to a preset first leakage concentration value and the indoor heat exchanger operates as a condenser.

[0006] On the other hand, an air conditioner is provided. The air conditioner includes an indoor heat exchanger, an outdoor heat exchanger, a compressor, an expansion valve, a first solenoid valve, a concentration sensor, and a controller. The first solenoid valve is disposed on a pipeline between the expansion valve and the indoor heat exchanger and is configured to regulate the flow rate of a flowing medium in the pipeline between the expansion valve and the indoor heat exchanger. The concentration sensor is configured to detect a current concentration value of a refrigerant in an indoor environment. The controller is configured to control the first solenoid valve to close when the indoor heat exchanger operates as an evaporator and the compressor operates at a target operating frequency; and when the current concentration value of the refrigerant detected by the concentration sensor is less than a preset concentration threshold, detect the current opening of the expansion valve and control the expansion valve to adjust to a preset target opening at an adjustment rate within a preset valve adjustment time. The adjustment rate is the ratio of the difference between the current opening and the target opening to the valve adjustment time. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] To more clearly illustrate the technical solutions of the present disclosure, the following briefly introduces the drawings required for use in some embodiments of the present disclosure. However, the drawings described below are only drawings of some embodiments of the present disclosure, and those skilled in the art can also derive other drawings based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams and are not intended to limit the actual size of the products involved in the embodiments of the present disclosure, the actual process of the method, the actual timing of the signals, etc.

[0008] FIG1A is a block diagram of an air conditioner according to some embodiments;

[0009] FIG1B is a structural diagram of an indoor unit of an air conditioner according to some embodiments;

[0010] FIG2 is a structural diagram of an air conditioner according to some embodiments;

[0011] FIG3 is a structural diagram of another air conditioner according to some embodiments;

[0012] FIG4 is a block diagram of another air conditioner according to some embodiments;

[0013] FIG5 is a flow chart of a controller of an air conditioner according to some embodiments;

[0014] FIG6 is a flow chart of a first recovery mode of an air conditioner according to some embodiments;

[0015] FIG7 is a flow chart of a second recovery mode of an air conditioner according to some embodiments;

[0016] FIG8 is a flow chart of another controller of an air conditioner according to some embodiments;

[0017] FIG9 is a flowchart of a controller of another air conditioner according to some embodiments. DETAILED DESCRIPTION

[0018] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present disclosure. Obviously, the embodiments described are only some embodiments of the present disclosure, not all embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present disclosure.

[0019] Unless the context requires otherwise, throughout the specification and claims, the term "comprise" and its other forms, such as the third person singular form "comprises" and the present participle form "comprising", are to be interpreted as open and inclusive, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example" or "some examples" are intended to indicate that the particular features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the particular features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner.

[0020] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

[0021] When describing some embodiments, the expressions "coupled" and "connected" and their derivatives may be used. The term "connected" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. The term "coupled" indicates that two or more components are in direct physical or electrical contact. The term "coupled" or "communicatively coupled" may also refer to two or more components that are not in direct contact with each other, but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the contents of this document.

[0022] “At least one of A, B and C” has the same meaning as “at least one of A, B or C” and both include the following combinations of A, B and C: A only, B only, C only, the combination of A and B, the combination of A and C, the combination of B and C, and the combination of A, B and C.

[0023] The use of "adapted to" or "configured to" herein is intended to be open and inclusive language that does not exclude devices adapted or configured to perform additional tasks or steps.

[0024] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of deviation from the particular value as determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0025] In the description of this application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position 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, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0026] With the widespread use of air conditioners, users are increasingly demanding environmentally friendly air conditioners. The air conditioner's refrigeration cycle relies on refrigerants. For example, R290 refrigerant is environmentally friendly and, as such, is widely used in air conditioners. However, R290 refrigerant is flammable, and leaks pose safety risks, such as explosions.

[0027] Air conditioners are typically equipped with anti-dismantling structures and warning labels. For example, installing an anti-dismantling structure on an air conditioner can prevent it from being disassembled indoors, thereby preventing refrigerant from leaking into the indoor environment. Warning labels posted on or near the air conditioner can alert indoor users to the dangers of refrigerant leaks.

[0028] However, it's understandable that the above configuration can't completely prevent refrigerant leaks during air conditioner operation. For example, installing an anti-disassembly structure on an air conditioner can prevent it from being disassembled a second time indoors, thereby preventing refrigerant leaks caused by improper reassembly. However, if a refrigerant leak already exists when the air conditioner is first installed, installing an anti-disassembly structure on the air conditioner won't effectively prevent it. Furthermore, posting a warning label only alerts those who pay attention to the label's content, but has very limited effectiveness for those who don't.

[0029] Methods for detecting refrigerant leaks include pressure testing and leak detection methods.

[0030] For example, when using a pressure test to detect refrigerant leaks, one or more pressure gauges are required in the air conditioner's refrigerant circuit. A refrigerant leak can be determined when any of the pressure gauges detects a rapid drop in refrigerant pressure in the refrigerant circuit. However, the pressure test method cannot pinpoint the location of the refrigerant leak and cannot accurately determine the presence of a refrigerant leak if the leak is minor.

[0031] For example, when using a leak detector to detect refrigerant leaks, a leak detector is added to the refrigerant circuit. The leak detector dyes the refrigerant, so that when a leak occurs, the leak detector leaks along with the refrigerant, alerting the user. However, adding a leak detector to the refrigerant can degrade refrigerant performance, such as reducing its cooling capacity. Furthermore, leaking the leak detector along with the refrigerant can pose a greater safety hazard.

[0032] Some embodiments of the present disclosure provide an air conditioner 1000, as shown in Figures 1A and 1B. The air conditioner 1000 includes an outdoor unit 1, an indoor unit 2, and an expansion valve 3. The outdoor unit 1 includes a compressor 11 and an outdoor heat exchanger 12. The indoor unit 2 includes an indoor heat exchanger 21. The expansion valve 3 can be provided in the outdoor unit 1 or the indoor unit 2.

[0033] The outdoor heat exchanger 12 and the indoor heat exchanger 21 can function as either an evaporator or a condenser. For example, when the outdoor heat exchanger 12 functions as an evaporator and the indoor heat exchanger 21 functions as a condenser, the air conditioner 1000 operates in a heating cycle. When the outdoor heat exchanger 12 functions as a condenser and the indoor heat exchanger 21 functions as an evaporator, the air conditioner 1000 operates in a cooling cycle.

[0034] Air conditioner 1000 performs a refrigeration cycle or a heating cycle through compressor 11, condenser, expansion valve 3, and evaporator. The refrigeration cycle and heating cycle include compression, condensation, expansion, and evaporation. During each of these cycles, the refrigerant absorbs or releases heat to cool or heat the indoor space, thereby regulating the indoor temperature.

[0035] Compressor 11 compresses the refrigerant gas to a high-temperature, high-pressure state and discharges it from compressor 11. The compressed refrigerant gas flows into the condenser. The condenser condenses the compressed, high-temperature, high-pressure gaseous refrigerant into liquid refrigerant, releasing the heat of the refrigerant into the surrounding environment through the condensation process.

[0036] The liquid refrigerant flowing out of the condenser enters the expansion valve 3, which expands the high-temperature, high-pressure liquid refrigerant condensed in the condenser into low-pressure liquid refrigerant. The low-pressure liquid refrigerant flowing out of the expansion valve 3 enters the evaporator. As it passes through the evaporator, it absorbs heat and evaporates into low-temperature, low-pressure refrigerant gas. The low-temperature, low-pressure refrigerant gas returns to the compressor 11.

[0037] The evaporator achieves a cooling effect by utilizing the latent heat of evaporation of the refrigerant to exchange heat with the material to be cooled. As the refrigerant circulates, the air conditioner 1000 can regulate the temperature of the indoor space. The indoor unit 2 also includes an air outlet 22, a first air guide plate 23, and a second air guide plate 24. The air outlet 22, the first air guide plate 23, and the second air guide plate 24 allow the refrigerant to exchange heat with the indoor environment, thereby lowering the indoor temperature.

[0038] In some embodiments, as shown in FIG. 2 and FIG. 3 , the air conditioner 1000 further includes a pipeline 4 , a first solenoid valve 51 , a second solenoid valve 52 , a first stop valve 61 , a second stop valve 62 and a four-way valve 7 .

[0039] Pipeline 4 is configured to connect indoor heat exchanger 21, outdoor heat exchanger 12, compressor 11, expansion valve 3, first solenoid valve 51, second solenoid valve 52, first stop valve 61, second stop valve 62, and four-way valve 7 to form a refrigerant circuit. Refrigerant circulates in the refrigerant circuit, exchanging heat with air through outdoor heat exchanger 12 and indoor heat exchanger 21, respectively, to achieve a cooling cycle or a heating cycle of air conditioner 1000.

[0040] The expansion valve 3 is connected between the indoor heat exchanger 21 and the outdoor heat exchanger 12 and is configured to expand the liquid refrigerant that has undergone the condensation process into a low-pressure liquid refrigerant. For example, the expansion valve 3 is an electronic expansion valve.

[0041] The first solenoid valve 51 is disposed in the pipeline 4 between the expansion valve 3 and the indoor heat exchanger 21 and is configured to regulate the flow rate of the flowing medium in the pipeline 4. The first shut-off valve 61 is disposed in the pipeline 4 between the first solenoid valve 51 and the indoor heat exchanger 21 and is configured to shut off and throttle the flowing medium in the pipeline 4 between the first solenoid valve 51 and the indoor heat exchanger 21.

[0042] The indoor heat exchanger 21 and the outdoor heat exchanger 12 are each connected to the compressor 11. For example, the indoor heat exchanger 21 and the outdoor heat exchanger 12 are each connected to the compressor 11 via a four-way valve 7. A second solenoid valve 52 is disposed in the pipeline 4 between the four-way valve 7 and the indoor heat exchanger 21 and is configured to regulate the flow rate of the fluid in the pipeline 4. A second shut-off valve 62 is disposed between the second solenoid valve 52 and the indoor heat exchanger 21 and is configured to shut off and throttle the fluid in the pipeline 4 between the second solenoid valve 52 and the indoor heat exchanger 21.

[0043] The indoor heat exchanger 21 includes a first communication port 211 and a second communication port 212. The first communication port 211 is connected to the first stop valve 61, and the second communication port 212 is connected to the second stop valve 62. The outdoor heat exchanger 12 includes a third communication port 121 and a fourth communication port 122. The third communication port 121 is connected to the expansion valve 3, and the fourth communication port 122 is connected to the four-way valve 7.

[0044] The compressor 11 includes an air intake 111 and an air discharge 112 . Refrigerant that has absorbed heat and evaporated enters the compressor 11 from the air intake 111 . The compressor 11 compresses the gaseous refrigerant into a high-temperature and high-pressure state and then discharges it from the air discharge 112 .

[0045] The four-way valve 7 includes a first valve port 71, a second valve port 72, a third valve port 73, and a fourth valve port 74. The first valve port 71 is fixedly connected to the air intake port 111, and the third valve port 73 is fixedly connected to the air exhaust port 112. When the air conditioner 1000 is in cooling mode, the first valve port 71 is connected to the second valve port 72, and the third valve port 73 is connected to the fourth valve port 74. When the air conditioner 1000 is in heating mode, the first valve port 71 is connected to the fourth valve port 74, and the second valve port 72 is connected to the third valve port 73.

[0046] The air conditioner 1000 further includes an exhaust gas sensor disposed in the pipeline 4 between the exhaust port 112 and the third valve port 73 and configured to measure the exhaust gas temperature of the compressor 11 .

[0047] The air conditioner 1000 includes a first operating mode (such as a cooling mode) and a second operating mode (such as a heating mode).

[0048] When the air conditioner 1000 operates in the first operation mode, the indoor heat exchanger 21 is used as an evaporator, and the outdoor heat exchanger 12 is used as a condenser.

[0049] The compressor 11 compresses the gaseous refrigerant into a high-temperature, high-pressure state and discharges the high-temperature, high-pressure refrigerant gas from the exhaust port 112. The high-temperature, high-pressure refrigerant gas enters the outdoor heat exchanger 12 via the four-way valve 7 and the fourth communication port 122, where it condenses, releasing the refrigerant's heat into the surrounding environment. The high-temperature, high-pressure refrigerant gas then condenses from a gaseous state to a liquid state and flows into the expansion valve 3 via the third communication port 121. The expansion valve 3 expands the high-pressure liquid refrigerant into a low-pressure liquid refrigerant.

[0050] The liquid refrigerant flowing out of the expansion valve 3 flows into the indoor heat exchanger 21 via the first solenoid valve 51, the first shut-off valve 61, and the first communication port 211. The low-pressure liquid refrigerant evaporates in the indoor heat exchanger 21 to exchange heat with the indoor environment, absorbing heat and changing from liquid to gas. The low-temperature, low-pressure refrigerant gas enters the compressor 11 via the second communication port 212, the second shut-off valve 62, the second solenoid valve 52, the four-way valve 7, and the intake port 111. The compressor 11 compresses the refrigerant gas from the low-temperature, low-pressure state to a high-temperature, high-pressure state and discharges it from the exhaust port 112. The high-temperature, high-pressure refrigerant gas enters the outdoor heat exchanger 12 again via the four-way valve 7 and the fourth communication port 122, and is condensed again in the outdoor heat exchanger 12.

[0051] In this way, when the air conditioner 1000 is operating in the first working mode, the refrigerant flowing through the indoor heat exchanger 21 absorbs heat by consuming the electric energy supplied to the compressor 11, thereby reducing the temperature of the indoor environment.

[0052] When the air conditioner 1000 operates in the second operating mode, the indoor heat exchanger 21 functions as a condenser, and the outdoor heat exchanger 12 functions as an evaporator. The compressor 11 compresses the gaseous refrigerant into a high-temperature, high-pressure state and discharges the high-temperature, high-pressure refrigerant gas from the exhaust port 112. The high-temperature, high-pressure refrigerant gas enters the indoor heat exchanger 21 via the four-way valve 7, the second solenoid valve 52, the second shut-off valve 62, and the second communication port 212. There, it condenses within the indoor heat exchanger 21, releasing the refrigerant's heat into the indoor environment, raising the indoor temperature. The high-temperature, high-pressure refrigerant gas undergoes condensation, transforming from a gas into a liquid state. The refrigerant then flows through the first communication port 211, the first shut-off valve 61, and the first solenoid valve 51 into the expansion valve 3. The expansion valve 3 expands the high-pressure liquid refrigerant into a low-pressure liquid refrigerant.

[0053] The liquid refrigerant flowing out of the expansion valve 3 flows into the outdoor heat exchanger 12 through the third communication port 121. The low-pressure liquid refrigerant evaporates in the outdoor heat exchanger 12, absorbing heat from the outdoor environment. As a result, the low-pressure liquid refrigerant evaporates into a low-temperature, low-pressure refrigerant gas. The low-temperature, low-pressure refrigerant gas enters the compressor 11 through the fourth communication port 122, the four-way valve 7, and the intake port 111. The compressor 11 compresses the refrigerant gas from its low-temperature, low-pressure state to a high-temperature, high-pressure state and discharges it through the exhaust port 112. The high-temperature, high-pressure refrigerant gas enters the indoor heat exchanger 21 again through the four-way valve 7, the second solenoid valve 52, the second shut-off valve 62, and the second communication port 212 to undergo a condensation process.

[0054] In this way, when the air conditioner 1000 is operated in the second operation mode, the refrigerant flowing through the indoor heat exchanger 21 dissipates heat by consuming the electric energy supplied to the compressor 11, thereby increasing the temperature of the indoor environment.

[0055] In some embodiments, as shown in FIG4 , the air conditioner 1000 further includes a concentration sensor 8 and a controller 9. The concentration sensor 8 is provided on the indoor unit 2 and is located at a position of the indoor unit 2 where refrigerant leakage is likely to occur. For example, the concentration sensor 8 is provided at the connection between the indoor heat exchanger 21 and the second stop valve 62, or at the connection between the first stop valve 61 and the indoor heat exchanger 21. The concentration sensor 8 is configured to detect a current concentration value A of the refrigerant and to send a detected signal representing the current concentration value A of the refrigerant to the controller 9. The controller 9 is connected to the compressor 11 and the concentration sensor 8, respectively, and is configured to receive the signal from the concentration sensor 8.

[0056] FIG5 is a flow chart of a controller 9 of an air conditioner 1000 according to some embodiments. As shown in FIG5 , the controller 9 is configured to execute steps 101 to 102 .

[0057] In step 101 , it is determined whether a refrigerant leak occurs.

[0058] In some embodiments, as shown in FIG4 , the concentration sensor 8 includes a control component 81. The control component 81 is configured to determine whether a refrigerant leak occurs based on a current refrigerant concentration value A detected by the concentration sensor 8, and to send a signal indicating a refrigerant leak to the controller 9 if a refrigerant leak is determined to occur.

[0059] For example, when the concentration sensor 8 detects that the indoor refrigerant concentration is greater than or equal to a first concentration threshold (a first leakage concentration value), the control component 81 determines that a refrigerant leak has occurred and sends a signal indicating a refrigerant leak to the controller 9. In this case, upon receiving the signal indicating a refrigerant leak, the controller 9 determines that a refrigerant leak has occurred. When the concentration sensor 8 detects that the current indoor refrigerant concentration value A is less than the first concentration threshold, the control component 81 determines that a refrigerant leak has not occurred and does not send a signal indicating a refrigerant leak to the controller 9.

[0060] It should be noted that the first concentration threshold is a value preset in the control component 81. The first concentration threshold can be adjusted according to actual needs, and this disclosure does not limit this.

[0061] For example, the first concentration threshold is a value lower than the lowest concentration at which the refrigerant may explode in an indoor environment. The refrigerant concentration value at which no explosion occurs in an indoor environment can be obtained through experimental results.

[0062] It is understandable that by setting the first concentration threshold to be lower than the minimum concentration value at which the refrigerant may explode in an indoor environment, an alarm can be issued and a refrigerant recovery mode can be executed when the refrigerant leakage is small, thereby reducing the risk of explosion caused by refrigerant leakage.

[0063] In some embodiments, the first concentration threshold is preset in the controller 9. The controller 9 receives a signal representing the current refrigerant concentration value A from the concentration sensor 8 and determines whether a refrigerant leak has occurred based on the signal. For example, the concentration sensor 8 detects the current refrigerant concentration value A and transmits a signal representing the current refrigerant concentration value A to the controller 9. The controller 9 determines whether a refrigerant leak has occurred based on the signal.

[0064] For example, when the controller 9 receives a signal representing the current refrigerant concentration value A from the concentration sensor 8, the controller 9 determines, based on the signal, whether the current refrigerant concentration value A is greater than or equal to the first concentration threshold. If the current refrigerant concentration value A is greater than or equal to the first concentration threshold, the controller 9 determines that a refrigerant leak has occurred. If the current refrigerant concentration value A is less than the first concentration threshold, the controller determines that no refrigerant leak has occurred.

[0065] In step 102 , the current operating mode of the air conditioner 1000 is determined, and the air conditioner 1000 is controlled to operate in the first recovery mode or the second recovery mode according to the current operating mode of the air conditioner 1000 .

[0066] During operation of the air conditioner 1000, when the controller 9 receives a signal from the concentration sensor 8 indicating a refrigerant leak, or when the controller 9 receives a signal from the concentration sensor 8 indicating a current refrigerant concentration value A and determines that the current refrigerant concentration value A is greater than or equal to the first concentration threshold, the controller 9 determines that a refrigerant leak has occurred. If the controller 9 determines that a refrigerant leak has occurred, the controller 9 controls the air conditioner 1000 to operate in a refrigerant recovery mode.

[0067] In some embodiments, the refrigerant recovery mode includes a first recovery mode and a second recovery mode. When the controller 9 determines that a refrigerant leak occurs, it determines the current operating mode of the air conditioner 1000 and controls the air conditioner 1000 to operate in the first recovery mode or the second recovery mode according to the current operating mode of the air conditioner 1000.

[0068] For example, when the air conditioner 1000 is operating in the first operating mode and the indoor heat exchanger 21 is used as an evaporator, the air conditioner 1000 simultaneously operates in the first recovery mode, adjusting the operating frequency of the compressor 11 to the target operating frequency F1 and maintaining the target operating frequency F1 to recover leaked refrigerant. When the air conditioner 1000 is operating in the second operating mode and the indoor heat exchanger 21 is used as a condenser, the air conditioner 1000 simultaneously operates in the second recovery mode, switching the operating mode of the air conditioner 1000 to the first operating mode, adjusting the operating frequency of the compressor 11 to the target operating frequency F1 and maintaining the target operating frequency F1 to recover leaked refrigerant.

[0069] FIG6 is a flow chart of a first recovery mode of an air conditioner 1000 according to some embodiments. In some embodiments, as shown in FIG6 , step 102 includes steps 201 to 205 .

[0070] In step 201 , it is determined whether the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1 . If so, step 202 is executed; otherwise, step 203 is executed.

[0071] It should be noted that the target operating frequency F1 is a value preset in the controller 9 and can be adjusted according to actual needs, which is not limited in this disclosure. For example, the target operating frequency F1 can be determined based on experimental results, simulation experiments, or theoretical calculations.

[0072] When the air conditioner 1000 is operating in the refrigerant recovery mode, the compressor 11 operates at the target operating frequency F1, which can accelerate the recovery of the refrigerant and maintain an appropriate pressure in the pipeline 4, thereby preventing the leakage of residual refrigerant in the indoor heat exchanger 21. For example, when the indoor heat exchanger 21 is used as an evaporator, the air conditioner 1000 is in the cooling mode, and the air conditioner 1000 is executing the first recovery mode, the controller 9 detects the current operating frequency F0 of the compressor 11 and determines the relationship between the current operating frequency F0 and the target operating frequency F1.

[0073] In step 202 , the operating frequency of the compressor 11 is controlled to decrease to the target operating frequency F1 at a frequency reduction rate V3 , and then the compressor 11 is controlled to maintain the target operating frequency F1 .

[0074] In some embodiments, when the air conditioner 1000 is operating in the first recovery mode, when the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1, the controller is also configured to control the operating frequency of the compressor 11 to decrease to the target operating frequency F1, and then control the compressor 11 to maintain the target operating frequency F1.

[0075] It should be noted that when the current operating frequency F0 of compressor 11 is greater than the target operating frequency F1, the operating frequency of compressor 11 is higher, and the refrigerant leakage rate is faster. Therefore, quickly reducing the operating frequency of compressor 11 to the target operating frequency F1 is beneficial for reducing the refrigerant leakage rate. Furthermore, operating the air conditioner 1000 in refrigerant recovery mode while compressor 11 is operating at the target operating frequency F1 is beneficial for rapidly recovering refrigerant, further reducing the indoor refrigerant leakage rate.

[0076] For example, when the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1, the controller 9 controls the operating frequency of the compressor 11 to be reduced to the target operating frequency F1 at a frequency reduction rate V3. The unit of the frequency reduction rate V3 is Hz / s. The frequency reduction rate V3 is a value preset in the controller 9.

[0077] It should be noted that the operating frequency of compressor 11 affects the refrigerant recovery rate. A higher frequency means more work is performed per unit time, rapidly compressing the low-temperature, low-pressure refrigerant gas entering compressor 11 into high-temperature, high-pressure refrigerant gas. This high-temperature, high-pressure refrigerant gas is then quickly delivered to outdoor heat exchanger 12, thereby increasing the refrigerant recovery rate. However, a higher frequency increases the refrigerant pressure within pipeline 4, which can accelerate the leakage of residual refrigerant from indoor heat exchanger 21.

[0078] The slower the frequency of compressor 11, the less work it performs per unit time. This causes the low-temperature, low-pressure refrigerant gas entering compressor 11 to be compressed more slowly into high-temperature, high-pressure refrigerant gas. This high-temperature, high-pressure refrigerant gas is then delivered more slowly to outdoor heat exchanger 12, thereby reducing the refrigerant recovery rate. However, the slower the operating frequency of compressor 11, the lower the refrigerant pressure in pipeline 4, which reduces the leakage rate of residual refrigerant in indoor heat exchanger 21.

[0079] Therefore, when the current operating frequency F0 of compressor 11 is greater than the target operating frequency F1, controller 9 controls the operating frequency of compressor 11 to decrease at a frequency reduction rate V3, allowing compressor 11 to quickly reduce its frequency to the target operating frequency F1. The rate of refrigerant leakage decreases as the operating frequency of compressor 11 decreases. Rapidly reducing the frequency of compressor 11 to the target operating frequency F1 allows for faster refrigerant recovery while reducing the amount of refrigerant leakage, thereby alleviating the safety risks caused by refrigerant leakage.

[0080] In addition, the controller 9 controls the compressor 11 to adjust the frequency to the target operating frequency F1 instead of stopping the air conditioner 1000 immediately, which can avoid damage to the compressor 11 caused by sudden shutdown and is beneficial to extending the service life of the air conditioner 1000.

[0081] In some embodiments, when the compressor 11 is operating, its operating frequency fluctuates within a certain frequency range. The frequency range includes a first frequency range and a second frequency range. Any frequency value in the first frequency range or the second frequency range is greater than the target operating frequency F1, and any frequency value in the first frequency range is closer to the target operating frequency F1 than any frequency value in the second frequency range.

[0082] In this way, when the air conditioner 1000 is running in the first recovery mode, when the controller 9 determines that the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1 and is in the first frequency range, the controller 9 is also configured to control the operating frequency of the compressor 11 to be reduced to the target operating frequency F1 at a frequency reduction rate V31, and then control the compressor 11 to maintain the target operating frequency F1.

[0083] When the controller 9 determines that the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1 and is in the second frequency range, the controller 9 is also configured to control the operating frequency of the compressor 11 to be reduced to the target operating frequency F1 at a frequency reduction rate V32, and then control the compressor 11 to maintain the target operating frequency F1.

[0084] For example, the frequency reduction rate V32 is greater than the frequency reduction rate V31.

[0085] It should be noted that when air conditioner 1000 operates in the first recovery mode, when the current operating frequency F0 of compressor 11 is greater than the target operating frequency F1 and is within the first frequency range, the degree of refrigerant leakage is low. In this case, the operating frequency of compressor 11 is reduced to the target operating frequency F1 at a slower frequency reduction rate V31, which helps maintain the stability of air conditioner 1000 operating in the first recovery mode, reduces losses in compressor 11, and extends the service life of compressor 11.

[0086] When the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1 and is within the second frequency range, the degree of refrigerant leakage is high. In this case, the operating frequency of the compressor 11 is reduced to the target operating frequency F1 at a relatively fast frequency reduction rate V32, which can quickly reduce the frequency in a relatively short period of time, thereby reducing the degree of refrigerant leakage and alleviating the safety risks caused by refrigerant leakage.

[0087] The frequency reduction rate V31 and the frequency reduction rate V32 are values ​​preset in the controller 9 and the unit is Hz / s.

[0088] To sum up, when the air conditioner 1000 is running in the first recovery mode, when the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1, the controller 9 determines the frequency range in which the current operating frequency F0 is located, and obtains the corresponding frequency reduction rate based on the frequency range in which the current operating frequency F0 is located, and controls the operating frequency of the compressor 11 to be reduced to the target operating frequency F1 at the corresponding frequency reduction rate.

[0089] In step 203 , it is determined whether the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1 . If so, step 204 is executed; otherwise, step 205 is executed.

[0090] In step 204 , the operating frequency of the compressor 11 is controlled to increase to the target operating frequency F1 at a frequency increase rate V4 , and then the compressor 11 is controlled to maintain the target operating frequency F1 .

[0091] In some embodiments, when the air conditioner 1000 is running in the first recovery mode, when the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1, the controller 9 is also configured to control the operating frequency of the compressor 11 to increase to the target operating frequency F1, and then control the compressor 11 to maintain the target operating frequency F1.

[0092] It is understood that when the current operating frequency F0 of compressor 11 is less than the target operating frequency F1, the operating frequency of compressor 11 is low, and the rate of refrigerant leakage is slow. However, the refrigerant recovery rate is slow due to the low operating frequency of compressor 11, which is not conducive to refrigerant recovery. In other words, the refrigerant recovery rate increases as the frequency of compressor 11 increases. When the current operating frequency F0 of compressor 11 is less than the target operating frequency F1, controller 9 controls the operating frequency of compressor 11 to increase to the target operating frequency F1, which is conducive to improving the refrigerant recovery rate.

[0093] For example, when the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1, the controller 9 controls the operating frequency of the compressor 11 to increase to the target operating frequency F1 at a frequency increase rate V4. The frequency increase rate V4 is a value preset in the controller 9 and is less than or equal to the frequency decrease rate V3. The unit of the frequency increase rate V4 is Hz / s.

[0094] Because the frequency increase rate V4 is less than or equal to the frequency decrease rate V3, compressor 11 can increase its frequency slowly. The rate of refrigerant leakage increases as the operating frequency of compressor 11 increases. A smaller frequency increase rate V4 for compressor 11 allows the operating frequency of compressor 11 to increase more slowly. Thus, while compressor 11 increases its frequency, refrigerant leaks slowly while its recovery rate is accelerated, minimizing the extent of refrigerant leakage and reducing the potential safety risks associated with refrigerant leakage.

[0095] In some embodiments, the frequency interval further includes a third frequency interval and a fourth frequency interval. Any frequency value in the third frequency interval and the fourth frequency interval is less than the target operating frequency F1, and any frequency value in the third frequency interval is closer to 0 than any frequency value in the fourth frequency interval.

[0096] Thus, when the air conditioner 1000 is operating in the first recovery mode, when the controller 9 determines that the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1 and is within the third frequency range, the controller 9 is further configured to control the operating frequency of the compressor 11 to increase to the target operating frequency F1 at a frequency increase rate V41, and then control the compressor 11 to maintain operation at the target operating frequency F1. When the controller 9 determines that the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1 and is within the fourth frequency range, the controller 9 is further configured to control the operating frequency of the compressor 11 to increase to the target operating frequency F1 at a frequency increase rate V42, and then control the compressor 11 to maintain operation at the target operating frequency F1. For example, the frequency increase rate V41 is greater than the frequency increase rate V42.

[0097] It should be noted that when air conditioner 1000 operates in the first recovery mode, when the current operating frequency F0 of compressor 11 is less than the target operating frequency F1 and is within the third frequency range, the degree of refrigerant leakage is high. In this case, the operating frequency of compressor 11 is increased to the target operating frequency F1 at a relatively fast frequency increase rate V41, allowing the frequency to be increased rapidly in a relatively short period of time, which helps reduce the degree of refrigerant leakage and accelerate the speed of refrigerant recovery, thereby reducing the safety risks caused by refrigerant leakage.

[0098] When the current operating frequency F0 of compressor 11 is less than the target operating frequency F1 and is within the fourth frequency range, the degree of refrigerant leakage is low. In this case, the operating frequency of compressor 11 is increased to the target operating frequency F1 at a slower frequency increase rate V42, which helps maintain the stability of air conditioner 1000 in the first recovery mode, reduces losses in compressor 11, and extends the service life of compressor 11.

[0099] The frequency increase rate V41 and the frequency increase rate V42 are values ​​preset in the controller 9 , and the unit is Hz / s.

[0100] To sum up, when the air conditioner 1000 is running in the first recovery mode, when the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1, the controller 9 determines the frequency range in which the current operating frequency F0 is located, and obtains the corresponding frequency increase rate based on the frequency range in which the current operating frequency F0 is located, and controls the operating frequency of the compressor 11 to increase to the target operating frequency F1 at the corresponding frequency increase rate.

[0101] In step 205 , the compressor 11 is controlled to maintain the target operating frequency F1 .

[0102] In some embodiments, when the air conditioner 1000 operates in the first recovery mode, when the current operating frequency F0 of the compressor 11 is equal to the target operating frequency F1, the controller 9 is further configured to control the compressor 11 to maintain the target operating frequency F1.

[0103] In summary, when controller 9 receives a signal from concentration sensor 8 indicating a refrigerant leak, or when controller 9 receives a signal from concentration sensor 8 indicating the current refrigerant concentration value A and determines that the current refrigerant concentration value A is greater than or equal to the first concentration threshold, controller 9 determines that a refrigerant leak has occurred, i.e., refrigerant within indoor unit 2 has leaked and diffused into the air. In this case, controller 9 controls air conditioner 1000 to operate in a refrigerant recovery mode, causing the refrigerant within indoor unit 2 to flow through pipeline 4 and be recovered to outdoor unit 1, thereby reducing the amount of refrigerant leakage.

[0104] That is, when the controller 9 determines that a refrigerant leak has occurred, the controller 9 controls the air conditioner 1000 to operate in the first recovery mode or the second recovery mode, causing the refrigerant in the indoor heat exchanger 21 to flow through the second shut-off valve 62, the second solenoid valve 52, and the air intake 111 into the compressor 11. The refrigerant is compressed into high-temperature, high-pressure refrigerant gas in the compressor 11 and then discharged from the exhaust 112 to the outdoor heat exchanger 12, gradually reducing the amount of refrigerant in the indoor heat exchanger 21 and the amount of refrigerant leakage. This allows the refrigerant to be recovered from the indoor heat exchanger 21, mitigating the safety risks associated with refrigerant leakage.

[0105] FIG7 is a flow chart of a second recovery mode of the air conditioner 1000 according to some embodiments. In some embodiments, as shown in FIG7 , step 102 includes steps 301 to 305 .

[0106] In step 301 , it is determined whether the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1 . If so, step 302 is executed; otherwise, step 303 is executed.

[0107] For example, when the indoor heat exchanger 21 is used as a condenser, the air conditioner 1000 is in a heating state, and the air conditioner 1000 runs in a second recovery mode, the controller 9 detects the current operating frequency F0 of the compressor 11 and determines the relationship between the current operating frequency F0 and the target operating frequency F1.

[0108] In step 302, the operating frequency of the compressor 11 is controlled to be reduced to the target operating frequency F1 at a frequency reduction rate V1, the four-way valve 7 is controlled to reverse so that the air conditioner 1000 switches from the heating mode to the cooling mode, and the compressor 11 is controlled to maintain the target operating frequency F1.

[0109] In some embodiments, when the air conditioner 1000 is operating in the second recovery mode, when the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1, the controller 9 is also configured to control the operating frequency of the compressor 11 to be reduced to the target operating frequency F1, and then control the four-way valve 7 to reverse so that the air conditioner 1000 switches to the cooling mode, so that the indoor heat exchanger 21 is used as an evaporator, and the compressor 11 is controlled to operate at the target operating frequency F1.

[0110] As mentioned above, when the air conditioner 1000 operates in the second recovery mode, the operating frequency of the compressor 11 should not be too large or too small. The air conditioner 1000 operates in the refrigerant recovery mode when the compressor 11 operates at the target operating frequency F1, which is conducive to rapid recovery of refrigerant.

[0111] For example, when the current operating frequency F0 of compressor 11 is greater than the target operating frequency F1, controller 9 controls compressor 11 to reduce its frequency to the target operating frequency F1 at a frequency reduction rate V1 (a first frequency reduction rate), and then controls four-way valve 7 to switch, switching air conditioner 1000 from a heating mode to a cooling mode. Frequency reduction rate V1 is expressed in Hz / s and is a value preset in controller 9. Frequency reduction rate V1 can be the same as or different from frequency reduction rate V3, and this is not limited in this disclosure.

[0112] It is understood that when the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1, the controller 9 controls the operating frequency of the compressor 11 to decrease at a frequency reduction rate V1, thereby quickly reducing the frequency of the compressor 11 to the target operating frequency F1. The rate of refrigerant leakage decreases as the operating frequency of the compressor 11 decreases. The rapid frequency reduction of the compressor 11 to the target operating frequency F1 allows for faster refrigerant recovery while reducing the amount of refrigerant leakage, thereby alleviating the safety risks caused by refrigerant leakage.

[0113] In some embodiments, the frequency interval further includes a fifth frequency interval and a sixth frequency interval. Any frequency value in the fifth frequency interval and the sixth frequency interval is greater than the target operating frequency F1, and any frequency value in the fifth frequency interval is closer to the target operating frequency F1 than any frequency value in the sixth frequency interval. The fifth frequency interval may be the same as or different from the first frequency interval, and the sixth frequency interval may be the same as or different from the second frequency interval, which is not limited in this disclosure.

[0114] Thus, when the air conditioner 1000 is operating in the second recovery mode, when the controller 9 determines that the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1 and is within the fifth frequency range, the controller 9 is further configured to control the operating frequency of the compressor 11 to decrease to the target operating frequency F1 at a frequency reduction rate V11 (a second frequency reduction rate), and then control the compressor 11 to maintain operation at the target operating frequency F1. When the controller 9 determines that the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1 and is within the sixth frequency range, the controller 9 is further configured to control the operating frequency of the compressor 11 to decrease to the target operating frequency F1 at a frequency reduction rate V12 (a third frequency reduction rate), and then control the compressor 11 to maintain operation at the target operating frequency F1. For example, the frequency reduction rate V12 is greater than the frequency reduction rate V11.

[0115] It should be noted that, when the air conditioner 1000 is operating in the second recovery mode, when the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1, and the current operating frequency F0 is within the fifth frequency range, the degree of refrigerant leakage is low. In this case, the operating frequency of the compressor 11 is reduced to the target operating frequency F1 at a slower frequency reduction rate V11, which is beneficial to maintaining the stability of the air conditioner 1000 operating in the second recovery mode, and is beneficial to reducing the loss of the compressor 11 and extending the service life of the compressor 11. When the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1, and the current operating frequency F0 is within the sixth frequency range, the degree of refrigerant leakage is high. In this case, the operating frequency of the compressor 11 is reduced to the target operating frequency F1 at a faster frequency reduction rate V12, which can quickly reduce the frequency in a shorter period of time, which is beneficial to reducing the degree of refrigerant leakage and reducing the safety hazards caused by refrigerant leakage.

[0116] Frequency reduction rate V11 and frequency reduction rate V12 are preset values ​​in the controller 9 and are expressed in Hz / s. Frequency reduction rate V11 may be the same as or different from frequency reduction rate V31, and frequency reduction rate V12 may be the same as or different from frequency reduction rate V32, which is not limited in this disclosure.

[0117] To sum up, when the air conditioner 1000 is running in the second recovery mode, when the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1, the controller 9 determines the frequency range in which the current operating frequency F0 is located, and obtains the corresponding frequency reduction rate based on the frequency range in which the current operating frequency F0 is located, and controls the operating frequency of the compressor 11 to be reduced to the target operating frequency F1 at the corresponding frequency reduction rate.

[0118] In some embodiments, as shown in FIG4 , the controller 9 is connected to the four-way valve 7. The controller 9 is further configured to control the switching of the four-way valve 7 to switch the operating mode of the air conditioner 1000. For example, when the controller 9 controls the switching of the four-way valve 7 to switch the air conditioner 1000 from the heating mode to the cooling mode, the first valve port 71 switches from being connected to the fourth valve port 74 to being connected to the second valve port 72, and the third valve port 73 switches from being connected to the second valve port 72 to being connected to the fourth valve port 74.

[0119] When the air conditioner 1000 is operating in the second recovery mode, the air conditioner 1000 is in the heating mode, and the second connecting port 212 is connected to the exhaust port 112. The compressor 11 discharges high-temperature, high-pressure refrigerant gas to the indoor heat exchanger 21. The indoor heat exchanger 21 is used as a condenser to condense the high-temperature, high-pressure gaseous refrigerant. The condensed refrigerant flows into the expansion valve 3 through the first connecting port 211. Because the refrigerant in the indoor heat exchanger 21 is not connected to the intake port 111, when the air conditioner 1000 is in the heating mode, the refrigerant in the indoor heat exchanger 21 cannot be pumped to the outdoor heat exchanger 12 by the compressor 11. In other words, when the air conditioner 1000 is in the heating mode and recovering refrigerant, it is necessary to switch the operating mode to the cooling mode so that the air conditioner 1000 can recover refrigerant in the cooling mode.

[0120] When air conditioner 1000 is in cooling mode, indoor heat exchanger 21 functions as an evaporator, and second communication port 212 communicates with intake port 111. When compressor 11 operates at target operating frequency F1, compressor 11 compresses the refrigerant gas entering indoor heat exchanger 21 via second communication port 212 and intake port 111 into high-temperature, high-pressure refrigerant gas, and discharges the refrigerant to outdoor heat exchanger 12. Outdoor heat exchanger 12 functions as a condenser, condensing the high-temperature, high-pressure refrigerant gas into liquid refrigerant, thereby recovering the refrigerant from indoor heat exchanger 21 to outdoor heat exchanger 12.

[0121] Furthermore, when the air conditioner 1000 is operating in the second recovery mode and the current operating frequency F0 of the compressor 11 is greater than the target operating frequency F1, the operating frequency of the compressor 11 is too high to directly switch the current operating mode of the air conditioner 1000. In other words, the controller 9 cannot directly control the reversal of the four-way valve 7 to switch the air conditioner 1000 from the heating mode to the cooling mode. Instead, the operating frequency of the compressor 11 must first be reduced to the target operating frequency F1, and then the four-way valve 7 must be reversed to switch the air conditioner 1000 from the heating mode to the cooling mode.

[0122] In step 303 , it is determined whether the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1 . If so, step 304 is executed; otherwise, step 305 is executed.

[0123] In step 304, the four-way valve 7 is controlled to reverse so that the air conditioner 1000 switches from the heating mode to the cooling mode, the operating frequency of the compressor 11 is controlled to increase to the target operating frequency F1 at the frequency increase rate V2, and the compressor 11 is controlled to maintain the target operating frequency F1.

[0124] In some embodiments, when the air conditioner 1000 is running in the second recovery mode, when the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1, the controller 9 is also configured to control the reversing of the four-way valve 7 to switch the air conditioner 1000 from the heating mode to the cooling mode, so that the indoor heat exchanger 21 is used as an evaporator, and then control the operating frequency of the compressor 11 to increase to the target operating frequency F1 at the frequency increase rate V2 (first frequency increase rate), and control the compressor 11 to operate at the target operating frequency F1.

[0125] It is understood that when the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1, the operating frequency of the compressor 11 is relatively low, and the controller 9 can control the four-way valve 7 to directly reverse, thereby switching the air conditioner 1000 from the heating mode to the cooling mode, thereby allowing the air conditioner 1000 to recover refrigerant in the cooling mode. In this way, there is no need to adjust the operating frequency of the compressor 11 before recovering the refrigerant, which is conducive to improving the efficiency of refrigerant recovery and reducing the rate of refrigerant leakage.

[0126] Therefore, when the air conditioner 1000 is running in the second recovery mode, when the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1, the controller 9 controls the four-way valve 7 to reverse, so that the air conditioner 1000 switches from the heating mode to the cooling mode, and then controls the operating frequency of the compressor 11 to increase to the target operating frequency F1 at the frequency increase rate V2.

[0127] For example, the frequency increase rate V2 is a value preset in the controller 9, and the frequency increase rate V2 is less than or equal to the frequency decrease rate V1. The unit of the frequency increase rate V2 is Hz / s. The frequency increase rate V2 can be the same as or different from the frequency increase rate V4, and this disclosure does not limit this.

[0128] It is understood that the rate of refrigerant leakage increases with the increase in the operating frequency of compressor 11. A slower frequency increase rate of compressor 11 can cause the operating frequency of compressor 11 to increase more slowly, thereby reducing the amount of refrigerant leakage during the frequency increase process. Since the refrigerant recovery rate increases with the increase in the frequency of compressor 11, when the current operating frequency F0 of compressor 11 is less than the target operating frequency F1, controller 9 controls the operating frequency of compressor 11 to increase to the target operating frequency F1, thereby accelerating the refrigerant recovery rate.

[0129] Therefore, the frequency increase rate V2 is less than or equal to the frequency decrease rate V1, allowing the compressor 11 to increase its frequency slowly. The rate of refrigerant leakage increases as the operating frequency of the compressor 11 increases. A smaller frequency increase rate V2 for the compressor 11 allows the operating frequency of the compressor 11 to increase more slowly. Thus, while the frequency of the compressor 11 increases, the refrigerant leaks slowly while the refrigerant recovery rate is accelerated, reducing the extent of refrigerant leakage and thereby alleviating the safety risks associated with refrigerant leakage.

[0130] In some embodiments, the frequency interval further includes a seventh frequency interval and an eighth frequency interval. Any frequency value in the seventh frequency interval and the eighth frequency interval is less than the target operating frequency F1, and any frequency value in the seventh frequency interval is closer to 0 than any frequency value in the eighth frequency interval. The seventh frequency interval may be the same as or different from the third frequency interval, and the eighth frequency interval may be the same as or different from the fourth frequency interval, which is not limited in this disclosure.

[0131] Thus, when the air conditioner 1000 is operating in the second recovery mode, when the controller 9 determines that the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1 and is within the seventh frequency range, the controller 9 is further configured to control the operating frequency of the compressor 11 to increase to the target operating frequency F1 at a frequency increase rate V21 (a second frequency increase rate), and then control the compressor 11 to maintain operation at the target operating frequency F1. When the controller 9 determines that the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1 and is within the eighth frequency range, the controller 9 is further configured to control the operating frequency of the compressor 11 to increase to the target operating frequency F1 at a frequency increase rate V22 (a third frequency increase rate), and then control the compressor 11 to maintain operation at the target operating frequency F1. For example, the frequency increase rate V21 is greater than the frequency increase rate V22.

[0132] It should be noted that when air conditioner 1000 operates in the second recovery mode, when the current operating frequency F0 of compressor 11 is less than the target operating frequency F1 and is within the seventh frequency range, the degree of refrigerant leakage is high. In this case, the operating frequency of compressor 11 is increased to the target operating frequency F1 at a relatively fast frequency increase rate V21, allowing the frequency to be increased rapidly in a relatively short period of time, which helps reduce the degree of refrigerant leakage and accelerate the speed of refrigerant recovery, thereby reducing the safety risks caused by refrigerant leakage.

[0133] When the current operating frequency F0 of compressor 11 is less than the target operating frequency F1 and is within the eighth frequency range, the degree of refrigerant leakage is low. In this case, the operating frequency of compressor 11 is increased to the target operating frequency F1 at a slower frequency increase rate V22, which helps maintain the stability of air conditioner 1000 in the second recovery mode, reduces losses in compressor 11, and extends the service life of compressor 11.

[0134] Frequency increase rate V21 and frequency increase rate V22 are preset values ​​in the controller 9 and are expressed in Hz / s. Frequency increase rate V21 may be the same as or different from frequency increase rate V41, and frequency increase rate V22 may be the same as or different from frequency increase rate V42, which is not limited in this disclosure.

[0135] To sum up, when the air conditioner 1000 is running in the second recovery mode, when the current operating frequency F0 of the compressor 11 is less than the target operating frequency F1, the controller 9 determines the frequency range in which the current operating frequency F0 is located, and obtains the corresponding frequency increase rate based on the frequency range in which the current operating frequency F0 is located, and controls the operating frequency of the compressor 11 to increase to the target operating frequency F1 at the corresponding frequency increase rate.

[0136] In step 305 , the compressor 11 is controlled to maintain the target operating frequency F1 .

[0137] In some embodiments, when the air conditioner 1000 operates in the second recovery mode, when the current operating frequency F0 of the compressor 11 is equal to the target operating frequency F1, the controller 9 is further configured to control the operating frequency of the compressor 11 to maintain the target operating frequency F1.

[0138] In some embodiments, when the air conditioner 1000 operates in the first recovery mode, the air conditioner 1000 is always in the cooling mode, and the controller 9 controls the operating frequency of the compressor 11 to be adjusted to the target operating frequency F1, and then controls the compressor 11 to operate at the target operating frequency F1. When the air conditioner 1000 operates in the second recovery mode, the operating mode of the air conditioner 1000 switches from the heating mode to the cooling mode, and the controller 9 controls the operating frequency of the compressor 11 to be adjusted to the target operating frequency F1, and then controls the compressor 11 to operate at the target operating frequency F1.

[0139] When the air conditioner 1000 is in cooling mode and the compressor 11 is operating at the target operating frequency F1, the refrigerant in the outdoor heat exchanger 12 flows into the indoor heat exchanger 21 via the first solenoid valve 51, and then flows back into the outdoor heat exchanger 12 via the second solenoid valve 52 and the compressor 11. This causes the recovered refrigerant to re-enter the indoor heat exchanger 21 and leak again. Therefore, it is necessary to close the first solenoid valve 51 to cut off the source of refrigerant flowing into the indoor heat exchanger 21 and prevent further leakage of the recovered refrigerant.

[0140] FIG8 is a flow chart of another controller 9 of an air conditioner 1000 according to some embodiments. In some embodiments, as shown in FIG8 , when the air conditioner 1000 operates in the first recovery mode or the second recovery mode, and the air conditioner 1000 is in the cooling mode, and the compressor 11 operates at the target operating frequency F1, the controller 9 is further configured to execute steps 401 to 408.

[0141] In step 401 , the first solenoid valve 51 is controlled to be closed.

[0142] In some embodiments, as shown in FIG4 , the controller 9 is connected to the first solenoid valve 51 . The controller 9 is further configured to control the opening and closing of the first solenoid valve 51 .

[0143] For example, when the air conditioner 1000 is running in the first recovery mode or the second recovery mode, and the air conditioner 1000 is in the cooling state, and the compressor 11 is running at the target operating frequency F1, the controller 9 controls the first solenoid valve 51 to close, so that the refrigerant in the outdoor unit 1 cannot flow to the indoor unit 2 through the first solenoid valve 51, thereby cutting off the source of refrigerant in the indoor unit 2.

[0144] When the first solenoid valve 51 is closed, cutting off the refrigerant supply to the indoor unit 2, the compressor 11 operates at the target operating frequency F1, allowing the refrigerant in the indoor unit 2 to continuously enter the compressor 11 and be compressed by the compressor 11 into a high-temperature, high-pressure gas, which is then transported to the outdoor unit 1. In this way, while the refrigerant supply to the indoor unit 2 is cut off, the amount of refrigerant in the indoor unit 2 is continuously reduced, thereby reducing refrigerant leakage from the indoor unit 2 and mitigating safety risks caused by refrigerant leakage.

[0145] In step 402 , it is determined whether the current concentration value A meets the first concentration threshold condition. If so, step 403 is executed; if not, step 406 is executed.

[0146] For example, the concentration sensor 8 detects the current concentration value A of the refrigerant and sends a signal representing the current concentration value A to the controller 9. The controller 9 receives the signal representing the current concentration value A sent by the concentration sensor 8 and determines the relationship between the current concentration value A and the first concentration threshold condition.

[0147] It should be noted that the first concentration threshold condition is preset in the controller 9. For example, the first concentration threshold condition is that the current concentration value A is greater than 0 and less than the preset concentration threshold C, that is, the current concentration value A∈(0, C). The preset concentration threshold C is twice the second leakage concentration value B, that is, C=2B. The second leakage concentration value B is a concentration value representing refrigerant leakage preset in the controller 9. The second leakage concentration value B is 0.035kg / m 3 Up to 0.040kg / m 3 Any value between, for example, 0.035kg / m 3 , 0.038kg / m 3 or 0.040kg / m 3 .

[0148] The controller 9 is further configured to control the air conditioner 1000 to operate in the third recovery mode when it is determined that the current concentration value A meets the first concentration threshold condition.

[0149] The controller 9 also presets a second concentration threshold condition, which is that the current concentration value A is greater than or equal to a preset concentration threshold C, i.e., the current concentration value A∈[C, +∞). The controller 9 is further configured to control the air conditioner 1000 to operate in the fourth recovery mode if it is determined that the current concentration value A satisfies the second concentration threshold condition.

[0150] In step 403, the current temperature difference X between the current ambient temperature Th and the current coil temperature Tp is calculated.

[0151] In some embodiments, the air conditioner 1000 further includes a room temperature sensor and a coil temperature sensor. The room temperature sensor is disposed in the indoor unit 2 and is connected to the controller 9. The room temperature sensor is configured to measure the current ambient temperature Th of the indoor environment and transmit a signal representing the current ambient temperature Th to the controller 9. The indoor heat exchanger 21 further includes a coil. The coil temperature sensor is disposed on the surface of the coil and is connected to the controller 9. The coil temperature sensor is configured to measure the current coil temperature Tp of the coil and transmit a signal representing the current coil temperature Tp to the controller 9.

[0152] When the controller 9 determines that the current concentration value A meets the first concentration threshold condition and controls the air conditioner 1000 to operate in the third recovery mode, the controller 9 is further configured to calculate the current temperature difference X. The current temperature difference X is the difference between the current ambient temperature Th and the current coil temperature Tp.

[0153] For example, when the controller 9 controls the air conditioner 1000 to operate in the third recovery mode, the room temperature sensor continuously transmits a signal representing the current ambient temperature Th to the controller 9, and the coil temperature sensor continuously transmits a signal representing the current coil temperature Tp to the controller 9. The controller 9 calculates a current temperature difference X between the current ambient temperature Th and the current coil temperature Tp.

[0154] In step 404 , it is determined whether the current temperature difference X is less than or equal to the preset temperature difference X0 . If so, step 405 is executed; if not, step 401 is executed again.

[0155] For example, when the controller 9 controls the air conditioner 1000 to operate in the third recovery mode and calculates the current temperature difference X between the current ambient temperature Th and the current coil temperature Tp, the controller 9 is further configured to determine the magnitude relationship between the current temperature difference X and a preset temperature difference X0. The preset temperature difference X0 is a value preset in the controller 9 and is any value between 0°C and 4°C, for example, 0°C, 2°C, or 4°C.

[0156] In step 405, the second solenoid valve 52 is controlled to be closed, and the air conditioner 1000 is controlled to be shut down.

[0157] In some embodiments, as shown in FIG4 , the controller 9 is further connected to the second solenoid valve 52 . The controller 9 is further configured to control the opening and closing of the second solenoid valve 52 .

[0158] For example, when the controller 9 controls the air conditioner 1000 to operate in the third recovery mode and determines that the current temperature difference X is less than or equal to the preset temperature difference X0, the controller 9 determines that the refrigerant recovery is complete. In this case, the controller 9 controls the second solenoid valve 52 to close, controls the operating frequency of the compressor 11 to drop to 0, and controls the air conditioner 1000 to shut down.

[0159] It is understood that if the current temperature difference X is less than or equal to the preset temperature difference X0, it indicates that the current coil temperature Tp is close to the current ambient temperature Th, and the refrigerant content in the coil is low. Therefore, when the controller 9 determines that the current temperature difference X is less than or equal to the preset temperature difference X0, it can be determined that refrigerant recovery has been completed. If the controller 9 determines that refrigerant recovery has been completed, the controller 9 controls the second solenoid valve 52 to close, controls the operating frequency of the compressor 11 to drop to 0, and controls the air conditioner 1000 to shut down.

[0160] It should be noted that, when the air conditioner 1000 is running in the third recovery mode, the controller 9 can determine whether the recovery of the refrigerant is completed based on the current temperature difference X. It can be understood that when the refrigerant content in the coil is small, the heat released by these refrigerants through heat exchange is small, which is not enough to cool the coil, thereby making the current temperature difference X smaller.

[0161] Since the coil has thermal inertia, the temperature of the coil starts to rise after the refrigerant recovery is completed. Therefore, when the current temperature difference X is less than or equal to the preset temperature difference X0, it can be determined that the refrigerant recovery is complete.

[0162] That is, when the current concentration value A meets the first concentration threshold condition, the refrigerant leakage is low, and the controller 9 determines that the refrigerant recovery is completed based on the current temperature difference X being less than or equal to the preset temperature difference X0, and controls the air conditioner 1000 to shut down.

[0163] When the current temperature difference X is greater than the preset temperature difference X0, the controller 9 controls the air conditioner 1000 to maintain the cooling state, which is beneficial to prolonging the cooling time of the air conditioner 1000.

[0164] In step 406 , the operating time of the compressor 11 is detected.

[0165] For example, when the controller 9 determines that the current concentration value A meets the second concentration threshold condition and controls the air conditioner 1000 to operate in the fourth recovery mode, the controller 9 is further configured to detect the operating time of the compressor 11 .

[0166] In step 407 , it is determined whether the operating time of the compressor 11 is greater than or equal to the rated time T. If so, step 408 is executed; if not, step 401 is executed again.

[0167] For example, when the controller 9 controls the air conditioner 1000 to operate in the fourth recovery mode, the controller 9 is further configured to determine whether the operating time of the compressor 11 is greater than or equal to the rated time T.

[0168] It should be noted that the rated time T is a value preset in the controller 9 and is data measured based on experimental results.

[0169] In step 408, the second solenoid valve 52 is controlled to be closed, and the air conditioner 1000 is controlled to be shut down.

[0170] For example, when controller 9 controls air conditioner 1000 to operate in the fourth recovery mode, the degree of refrigerant leakage is high. In this case, when controller 9 controls compressor 11 to operate at target operating frequency F1 for rated time T, and determines that compressor 11 has operated for greater than or equal to rated time T, controller 9 determines that the refrigerant recovery process has been completed. When air conditioner 1000 operates in the fourth recovery mode and controller 9 determines that the refrigerant recovery process has been completed, controller 9 controls second solenoid valve 52 to close, controls the operating frequency of compressor 11 to drop to 0, and controls air conditioner 1000 to shut down.

[0171] In some embodiments, when a refrigerant leak occurs, the current concentration value A detected by the concentration sensor 8 fluctuates within a certain concentration threshold interval. The concentration threshold interval includes a first concentration threshold interval and a second concentration threshold interval. Any concentration value in the first concentration threshold interval or the second concentration threshold interval is greater than twice the leakage concentration value B, and any concentration value in the first concentration threshold interval is closer to twice the leakage concentration value B than any concentration value in the second concentration threshold interval.

[0172] Thus, when the controller 9 controls the air conditioner 1000 to operate in the fourth recovery mode and the current concentration value A is within the first concentration threshold interval, the controller 9 is further configured to control the compressor 11 to operate at the target operating frequency F1 for a rated time T1. When the controller 9 controls the air conditioner 1000 to operate in the fourth recovery mode and the current concentration value A is within the second concentration threshold interval, the controller 9 is further configured to control the compressor 11 to operate at the target operating frequency F1 for a rated time T2. For example, the rated time T1 is less than the rated time T2.

[0173] It should be noted that when the air conditioner is operating in the fourth recovery mode, when the current concentration value A is within the first concentration threshold range, the degree of refrigerant leakage is low. In this case, the compressor 11 operates at the target operating frequency F1 for the rated time T1, which can complete refrigerant recovery in a shorter time, thereby facilitating energy conservation. When the current concentration value A is within the second concentration threshold range, the degree of refrigerant leakage is high. In this case, the compressor 11 operates at the target operating frequency F1 for the rated time T2, which can achieve more complete refrigerant recovery and reduce the safety risks caused by refrigerant leakage.

[0174] The setpoint time T1 and the setpoint time T2 are values ​​preset in the controller 9 .

[0175] To sum up, when the controller 9 determines that the current concentration value A meets the second preset concentration threshold condition and controls the air conditioner 1000 to operate in the fourth recovery mode, the controller 9 determines the concentration threshold interval in which the current concentration value A is located, and obtains the corresponding rated time based on the concentration threshold interval in which the current concentration value A is located, and controls the compressor 11 to operate at the target operating frequency F1 for the corresponding rated time.

[0176] In some embodiments, when the air conditioner 1000 is operating in the first recovery mode or the second recovery mode, and the air conditioner 1000 is in cooling mode, with the compressor 11 operating at the target operating frequency F1, the controller 9 controls the first solenoid valve 51 to close, preventing refrigerant from flowing into the indoor heat exchanger 21, thereby reducing refrigerant leakage. However, the first solenoid valve 51 may be damaged. If the first solenoid valve 51 is damaged and cannot be closed, refrigerant may flow into the indoor heat exchanger 21, causing further refrigerant leakage. In this case, the expansion valve 3 can be controlled to close, thereby cutting off the refrigerant supply to the indoor heat exchanger 21.

[0177] As shown in FIG. 9 , after step 402 and before step 403 , the controller 9 is further configured to execute steps 402A to 402C.

[0178] In step 402A, the current opening degree Sn of the expansion valve 3 is detected.

[0179] As shown in FIG4 , the controller 9 is connected to the expansion valve 3. The controller 9 is further configured to detect the current opening Sn of the expansion valve 3. For example, when the controller 9 determines that the current concentration value A meets the first concentration threshold condition and controls the air conditioner 1000 to operate in the third recovery mode, the controller 9 detects the current opening Sn of the expansion valve 3.

[0180] In step 402B, the adjustment rate V of the expansion valve 3 when it is adjusted from the current opening Sn to the target opening S0 within the valve adjustment time Tx is calculated.

[0181] In some embodiments, the controller 9 presets the target opening S0 and the valve adjustment time Tx. The controller 9 is further configured to calculate the adjustment rate V of the expansion valve 3 when adjusting from the current opening Sn to the target opening S0 within the valve adjustment time Tx.

[0182] For example, when the current opening difference between the current opening Sn and the target opening S0 is S1, the adjustment rate V is the ratio of the current opening difference S1 to the valve adjustment time Tx.

[0183] In step 402C, the expansion valve 3 is controlled to adjust its opening to the target opening S0 at the adjustment rate V within the valve adjustment time Tx.

[0184] For example, when the adjustment rate V is calculated, the controller 9 is further configured to control the expansion valve 3 to adjust the opening degree to the target opening degree S0 at the adjustment rate V within the valve adjustment time Tx.

[0185] When the current opening Sn is greater than the target opening S0, since the expansion valve 3 is connected to the pipe 4 through which the refrigerant flows from the outdoor heat exchanger 12 to the indoor heat exchanger 21, the controller 9 controls the expansion valve 3 to adjust from the current opening Sn to the target opening S0, which can reduce the flow of refrigerant flowing from the outdoor unit 1 to the indoor unit 2, so that the inflow of refrigerant in the indoor heat exchanger 21 is less than the outflow of refrigerant, thereby continuously reducing the total amount of refrigerant in the indoor heat exchanger 21 and realizing the recovery of the refrigerant.

[0186] When the current opening degree Sn is equal to the target opening degree S0, the controller 9 controls the opening degree of the expansion valve 3 to remain unchanged.

[0187] When the current opening Sn is less than the target opening S0, since the expansion valve 3 is connected to the pipe 4 through which the refrigerant flows from the outdoor heat exchanger 12 to the indoor heat exchanger 21, the controller 9 controls the expansion valve 3 to adjust from the current opening Sn to the target opening S0, so that the opening of the expansion valve 3 becomes larger, which can speed up the recovery of the refrigerant.

[0188] It should be noted that the greater the ratio of liquid refrigerant to the total amount of refrigerant in the air conditioner 1000, the greater the risk of liquid hammer in the compressor 11. Increasing the opening of the expansion valve 3 can reduce the proportion of liquid refrigerant in the air conditioner 1000 and reduce the risk of liquid hammer in the compressor 11.

[0189] Since the expansion valve 3 is connected between the third connecting port 121 and the first connecting port 211, the controller 9 controls the opening of the expansion valve 3 according to the adjustment rate V, and can gradually reduce the flow of refrigerant delivered from the outdoor heat exchanger 12 to the indoor heat exchanger 21 within the valve adjustment time Tx, thereby avoiding the impact on the air-conditioning system caused by the sudden closing of the expansion valve 3, thereby shortening the service life of the air conditioner 1000.

[0190] When the third recovery mode is completed, the controller 9 is also configured to control the expansion valve 3 to adjust from the target opening S0 to closed, that is, to control the opening of the expansion valve 3 to be adjusted to zero, so as to cut off the refrigerant source in the indoor heat exchanger 21, so that the refrigerant flowing out of the third connecting port 121 is cut off by the closed expansion valve 3 and cannot flow into the indoor heat exchanger 21, thereby preventing the recovered refrigerant from entering the indoor heat exchanger 21 again and then leaking again.

[0191] Because controller 9 controls the closing of first solenoid valve 51 before air conditioner 1000 enters the third recovery mode and controls the closing of expansion valve 3 after the third recovery mode is complete, the flow path for refrigerant from outdoor heat exchanger 12 to indoor heat exchanger 21 is closed by both expansion valve 3 and first solenoid valve 51. This prevents refrigerant in outdoor heat exchanger 12 from flowing to indoor heat exchanger 21, effectively preventing the refrigerant from being blocked due to damage to either expansion valve 3 or first solenoid valve 51.

[0192] Those skilled in the art will understand that the scope of the present invention is not limited to the above specific embodiments, and that certain elements of the embodiments may be modified and replaced without departing from the spirit of the present application. The scope of the present application is limited by the appended claims.

Claims

1. An air conditioner, comprising: Indoor heat exchanger; outdoor heat exchanger; a compressor configured to compress a gaseous refrigerant; a concentration sensor, disposed indoors and configured to detect a current concentration value of the refrigerant in the indoor environment; as well as The controller is configured as: When the current concentration value of the refrigerant detected by the concentration sensor is greater than or equal to a preset first leakage concentration value, and the indoor heat exchanger operates as an evaporator, controlling the air conditioner to operate in a first recovery mode; as well as When the current concentration value of the refrigerant detected by the concentration sensor is greater than or equal to a preset first leakage concentration value and the indoor heat exchanger operates as a condenser, the air conditioner is controlled to operate in a second recovery mode.

2. The air conditioner according to claim 1, wherein The first recycling mode includes: The controller detects the current operating frequency of the compressor; When the current operating frequency is greater than the target operating frequency, the controller controls the operating frequency of the compressor to decrease to the target operating frequency, and controls the compressor to operate at the target operating frequency; and When the current operating frequency is lower than the target operating frequency, the controller controls the operating frequency of the compressor to increase to the target operating frequency, and controls the compressor to operate at the target operating frequency.

3. The air conditioner according to claim 1 or 2, further comprising a four-way valve, wherein the four-way valve is connected to the controller, and the indoor heat exchanger and the outdoor heat exchanger are respectively connected to the compressor through the four-way valve; The second recycling mode includes: The controller detects the current operating frequency of the compressor; When the current operating frequency is greater than the target operating frequency, the controller controls the operating frequency of the compressor to decrease to the target operating frequency, controls the compressor to operate at the target operating frequency, and controls the four-way valve to switch so that the indoor heat exchanger operates as the evaporator; and When the current operating frequency is less than the target operating frequency, the controller controls the four-way valve to reverse so that the indoor heat exchanger operates as the evaporator, controls the operating frequency of the compressor to increase to the target operating frequency, and controls the compressor to operate at the target operating frequency.

4. The air conditioner according to claim 3, wherein: When the controller controls the air conditioner to operate in the first recovery mode or the second recovery mode, the controller is further configured to: When the current operating frequency is greater than the target operating frequency, controlling the operating frequency of the compressor to decrease to the target operating frequency at a first frequency reduction rate; and When the current operating frequency is lower than the target operating frequency, controlling the operating frequency of the compressor to increase to the target operating frequency at a first frequency increase rate; The first frequency increase rate is less than or equal to the first frequency decrease rate.

5. The air conditioner according to claim 3, wherein The concentration sensor includes a control component, in which the first leakage concentration value is preset; the control component is configured to send a signal indicating refrigerant leakage to the controller when the current concentration value of the refrigerant detected by the concentration sensor is greater than or equal to the first leakage concentration value; The controller is further configured to receive the signal representing refrigerant leakage, determine that refrigerant leakage occurs, and control the air conditioner to operate in the first recovery mode or the second recovery mode.

6. The air conditioner according to claim 3, wherein: The controller is preset with the first leakage concentration value; the concentration sensor is further configured to send a signal representing the current concentration value of the refrigerant to the controller; The controller is further configured to determine that refrigerant leakage occurs when the current concentration value of the refrigerant detected by the concentration sensor is greater than or equal to the first leakage concentration value, and control the air conditioner to operate in the first recovery mode or the second recovery mode.

7. The air conditioner according to claim 1, further comprising: Four-way valve; Expansion valve; a pipeline, through which the indoor heat exchanger, the outdoor heat exchanger, the compressor, the four-way valve, and the expansion valve are connected; a first solenoid valve, the first solenoid valve being disposed on a pipeline between the expansion valve and the indoor heat exchanger and configured to regulate a flow rate of a flowing medium in the pipeline between the expansion valve and the indoor heat exchanger; and A first stop valve is provided on the pipeline between the first solenoid valve and the indoor heat exchanger and is configured to cut off and throttle a flow medium in the pipeline between the first solenoid valve and the indoor heat exchanger.

8. The air conditioner according to claim 7, further comprising: a second solenoid valve, which is disposed on the pipeline between the four-way valve and the indoor heat exchanger and is configured to regulate the flow rate of the flowing medium in the pipeline between the four-way valve and the indoor heat exchanger, and a second stop valve, the second stop valve being disposed on the pipeline between the second solenoid valve and the indoor heat exchanger and being configured to cut off and throttle a flowing medium in the pipeline between the second solenoid valve and the indoor heat exchanger; Wherein, the first solenoid valve and the second solenoid valve are respectively connected to the controller.

9. The air conditioner according to claim 8, wherein The indoor heat exchanger includes a first connecting port and a second connecting port, the first connecting port is connected to the first stop valve, and the second connecting port is connected to the second stop valve; the outdoor heat exchanger includes a third connecting port and a fourth connecting port, the third connecting port is connected to the expansion valve, and the fourth connecting port is connected to the four-way valve.

10. The air conditioner according to any one of claims 3 to 9, wherein: The four-way valve includes a first valve port, a second valve port, a third valve port and a fourth valve port, and the compressor includes an air intake port connected to the first valve port and an air discharge port connected to the third valve port; When the indoor heat exchanger works as an evaporator, the first valve port is connected to the second valve port, and the third valve port is connected to the fourth valve port; When the indoor heat exchanger operates as a condenser, the first valve port is connected to the fourth valve port, and the second valve port is connected to the third valve port.

11. An air conditioner comprising: Indoor heat exchanger; outdoor heat exchanger; compressor; Expansion valve; a first solenoid valve, disposed on a pipeline between the expansion valve and the indoor heat exchanger, and configured to regulate a flow rate of a flowing medium in the pipeline between the expansion valve and the indoor heat exchanger; a concentration sensor configured to detect a current concentration value of the refrigerant in the indoor environment; as well as The controller is configured as: When the indoor heat exchanger operates as an evaporator and the compressor operates at a target operating frequency, controlling the first solenoid valve to close; and When the current concentration value of the refrigerant detected by the concentration sensor is less than a preset concentration threshold, detecting the current opening of the expansion valve, and controlling the expansion valve to adjust to a preset target opening at an adjustment rate within a preset valve adjustment time; The adjustment rate is the ratio of the difference between the current opening and the target opening to the valve adjustment time.

12. The air conditioner according to claim 11, wherein The controller is respectively connected to the concentration sensor, the compressor, the expansion valve and the first solenoid valve; A second leakage concentration value is preset in the controller, and the controller is further configured to determine that refrigerant leakage occurs when the current concentration value of the refrigerant detected by the concentration sensor is greater than or equal to the second leakage concentration value; The preset concentration threshold is twice the second leakage concentration value.

13. The air conditioner according to claim 12, wherein The indoor heat exchanger includes a coil; The air conditioner further comprises: a room temperature sensor configured to measure a current ambient temperature in the room and send a signal representing the current ambient temperature to the controller; and a coil temperature sensor configured to measure a current coil temperature of the coil and send a signal representing the current coil temperature to the controller; The controller is further configured to: When the current concentration value of the refrigerant detected by the concentration sensor is less than the preset concentration threshold, calculating a current temperature difference between the current ambient temperature and the current coil temperature; and When the current temperature difference is less than or equal to the preset temperature difference, it is determined that the refrigerant recovery is completed.

14. The air conditioner according to claim 13, wherein The controller is further configured to: When the current concentration value of the refrigerant detected by the concentration sensor is greater than or equal to the preset concentration threshold, detecting the operating time of the compressor; and When the operation time of the compressor is greater than or equal to a preset rated time, it is determined that the refrigerant recovery is completed.

15. The air conditioner according to claim 14, wherein When the controller determines that the refrigerant recovery is completed, the controller is further configured to control the expansion valve to be adjusted from the target opening degree to be closed.

16. The air conditioner according to claim 11, further comprising: a pipeline, the indoor heat exchanger, the outdoor heat exchanger, the compressor, and the expansion valve being connected via the pipeline; A first stop valve is provided on the pipeline between the first solenoid valve and the indoor heat exchanger and is configured to cut off and throttle a flow medium in the pipeline between the first solenoid valve and the indoor heat exchanger.

17. The air conditioner according to claim 16, further comprising: A four-way valve, wherein the indoor heat exchanger and the outdoor heat exchanger are respectively connected to the compressor through the four-way valve; a second solenoid valve, which is disposed on the pipeline between the four-way valve and the indoor heat exchanger and is configured to regulate the flow rate of the flowing medium in the pipeline between the four-way valve and the indoor heat exchanger, and A second stop valve is provided on the pipeline between the second solenoid valve and the indoor heat exchanger and is configured to cut off and throttle the flow medium in the pipeline between the second solenoid valve and the indoor heat exchanger.

18. The air conditioner according to claim 17, wherein The four-way valve includes a first valve port, a second valve port, a third valve port and a fourth valve port, and the compressor includes an air intake port connected to the first valve port and an air discharge port connected to the third valve port; When the indoor heat exchanger works as an evaporator, the first valve port is connected to the second valve port, and the third valve port is connected to the fourth valve port; When the indoor heat exchanger operates as a condenser, the first valve port is connected to the fourth valve port, and the second valve port is connected to the third valve port.

19. The air conditioner according to claim 17, wherein The second solenoid valve is connected to the controller; When the controller determines that the refrigerant recovery is completed, the controller is further configured to control the second solenoid valve to close and control the air conditioner to stop.

20. The air conditioner according to any one of claims 17 to 19, wherein: The indoor heat exchanger includes a first connecting port and a second connecting port, the first connecting port is connected to the first stop valve, and the second connecting port is connected to the second stop valve; the outdoor heat exchanger includes a third connecting port and a fourth connecting port, the third connecting port is connected to the expansion valve, and the fourth connecting port is connected to the four-way valve.

Images