WO2020155474A1

WO2020155474A1 - Compressor oil recovery system and method for air conditioning system, and refrigerant recovery and filling machine

Info

Publication number: WO2020155474A1
Application number: PCT/CN2019/087604
Authority: WO
Inventors: 姜红运
Original assignee: 深圳市泰路科技有限公司
Priority date: 2019-02-01
Filing date: 2019-05-20
Publication date: 2020-08-06
Also published as: CN109764578A

Abstract

Disclosed herein are a compressor oil recovery system and method for an air conditioning system, and a refrigerant recovery and filling machine, the refrigerant recovery and filling machine comprising a first port and a second port. The refrigerant recovery and filling machine is configured to: fill liquid refrigerants into the air conditioning system by means of the first port so as to dissolve compressor oil of the air conditioning system, recover a mixture of the refrigerants and the compressor oil from the air conditioning system by means of the second port thereof, fill the liquid refrigerant into the air conditioning system by means of the second port, so as to dissolve the compressor oil of the air conditioning system, and recover a mixture of the refrigerant and the compressor oil from the air conditioning system by means of the first port.

Description

Compressor oil recovery system and method of air conditioning system, and refrigerant recovery and filling machine

This disclosure claims the priority of a Chinese patent application filed with the Chinese Patent Office with an application number of 201910104857.0 on February 1, 2019. The entire content of this application is incorporated into this disclosure by reference.

Technical field

The present disclosure relates to the technical field of air conditioning compressor oil recovery, for example, to a compressor oil recovery system and method of an air conditioning system, and a refrigerant recovery filling machine.

Background technique

In the air conditioning system, the fluid medium is mainly composed of refrigerant and compressor oil, and the refrigerant and compressor oil are in a mixed and dissolved state. The refrigerant is driven by the compressor to evaporate (convert from liquid to gas to lower the ambient temperature) and condense (convert from gas to liquid to dissipate heat) in the air conditioning circuit. Compressor oil provides lubrication for the compressor. In the air-conditioning circuit, additives used for different functions, such as plugging agents, UV dyes for detecting leakage, and synergists to promote cooling, are dissolved in the compressor oil and circulate in the air-conditioning circuit with the main fluid medium. In addition, the pollutants that may damage the air conditioning system, such as moisture, acidic substances and metal powder, are also easily mixed in the compressor oil.

When the air-conditioning system is regularly maintained, the refrigerant is recovered through the refrigerant recovery and filling machine. However, the amount of compressor oil carried during refrigerant recovery is limited, it is difficult to recover all the compressor oil, and it is impossible to determine the amount of remaining compressor oil in the air conditioning system.

In addition, in most cases, repairing the air conditioning system involves replacing air conditioning components. The air conditioning system loop usually consists of a compressor, condenser, filter dryer, expansion valve and evaporator. Compressor oil is distributed in the compressor, condenser, filter dryer and evaporator. However, it is difficult to determine the proportion of compressor oil in each part of the air conditioning circuit. This is because, for example, for different automobile manufacturers and models, the proportion of compressor oil in each part of the air conditioning circuit is very different.

Therefore, when repairing the air-conditioning system involves replacing air-conditioning components, it is difficult to determine the amount of compressor oil loss of the air-conditioning system caused by the replacement of the components. Moreover, after air conditioning maintenance or repair, it is difficult to determine the amount of compressor oil in the air conditioning system, and because it is difficult to deal with the contaminants in the compressor oil in the air conditioning system, the air conditioning system needs repeated maintenance.

Therefore, this article hopes to provide a method and system that can recover all compressor oil from the air conditioning system as much as possible to overcome the above shortcomings.

Summary of the invention

This article proposes a compressor oil recovery system and method for an air conditioning system with a good recovery effect for the compressor oil of an air conditioning system, and a refrigerant recovery filling machine.

This article proposes a refrigerant recovery and filling machine, comprising a first port and a second port; wherein the refrigerant recovery and filling machine is configured to be at least one of the following: filling the air conditioning system through the first port The liquid refrigerant is used to dissolve the compressor oil of the air conditioning system, and the mixture of refrigerant and compressor oil is recovered from the air conditioning system through the second port; and the liquid refrigerant is added to the air conditioning system through the second port to The compressor oil of the air conditioning system is dissolved, and the mixture of refrigerant and compressor oil is recovered from the air conditioning system through the first port.

This article also proposes a compressor oil recovery system for air conditioning systems, including:

Air conditioning system; and

A refrigerant recovery and filling machine, wherein the refrigerant recovery and filling machine is the above-mentioned refrigerant recovery and filling machine, and two ports of the refrigerant recovery and filling machine are respectively communicated with the air conditioning system through a control valve.

This article also proposes a compressor oil recovery method for an air-conditioning system. The method includes at least one of the following: injecting liquid refrigerant into the air-conditioning system from a first direction to dissolve the compressor oil of the air-conditioning system; Recover the mixture of refrigerant and compressor oil in the system; and, inject liquid refrigerant into the air conditioning system from the second direction to dissolve the compressor oil of the air conditioning system, and recover the refrigerant and compressor from the air conditioning system from the first direction Oil mixture.

Description of the drawings

Figure 1 is a schematic structural diagram of a compressor oil recovery system of an air conditioning system according to an embodiment;

Figure 2 is a schematic structural diagram of the internal structure of a refrigerant recovery and filling machine according to an embodiment;

Figure 3 is a schematic structural diagram of a compressor oil separation device according to an embodiment;

Figure 4 is a structural block diagram of the control system of an embodiment;

5 is a flowchart of a method for recovering compressor oil in an air conditioning system according to an embodiment;

Figure 6 is a flowchart of step A in Figure 5;

Figure 7 is a flowchart of step B in Figure 5;

FIG. 8 is a flowchart of step B10 in FIG. 7;

Figure 9 is a flowchart of step B20 in Figure 7;

Figure 10 is a flowchart of step C in Figure 5;

FIG. 11 is a schematic structural diagram of an electronic device provided by an embodiment.

Reference signs:

100. Air conditioning system; 200. Refrigerant recovery and filling machine; 300. Control system;

101. Second compressor; 102, condenser; 103, expansion valve; 104, evaporator; 105, control valve eleven; 106, control valve twelve; 107, high pressure side; 108, low pressure side;

201. Compressor oil separation device; 202, first compressor; 203, refrigerant storage tank; 204, new compressor oil container; 205, new oil weighing sensor; 206, refrigerant weighing sensor; 207, pressure sensor; 208 , High pressure switch; 209, vacuum pump; 210, control valve one; 211, control valve two; 212, control valve three; 213, control valve four; 214, control valve nine; 215, control valve ten; 216, control valve thirteen ; 217, one-way valve; 2011, oil and gas separator; 2012, buffer container; 2013, old oil container; 2014, control valve five; 2015, control valve six; 2016, control valve seven; 2017, control valve eight; 2031 Liquid refrigerant outlet; 2032, refrigerant recovery inlet; 20111, the inlet of the oil and gas separator; 2012, the gaseous refrigerant inlet; 20113, the refrigerant outlet of the oil and gas separator; 20114, the oil outlet of the oil and gas separator;

301, controller; 302, display device; 303, input device.

detailed description

The technical solutions of this document will be further explained below in conjunction with the drawings and embodiments.

This article provides a compressor oil recovery system of an air conditioning system. As shown in FIGS. 1 to 4, the compressor oil recovery system of the air conditioning system includes an air conditioning system 100, a refrigerant recovery filling machine 200 and a control system 300. The air-conditioning system 100 may be an air-conditioning system for a vehicle, or other air-conditioning systems that need to recover compressor oil. In this embodiment, an air-conditioning system for a vehicle is described as an example.

During regular maintenance of the air-conditioning system, the refrigerant is recovered through the drying and filtering device of the refrigerant recovery and filling machine, oil-gas separation, and filtration and purification. The processed clean refrigerant is stored in the refrigerant tank, and finally the refrigerant is charged from the refrigerant tank to the air-conditioning system in. However, the amount of compressor oil carried during refrigerant recovery is limited, it is difficult to recover all the compressor oil, and it is impossible to determine the amount of remaining compressor oil in the air conditioning system.

FIG. 1 is a schematic structural block diagram of a compressor oil recovery system of an air conditioning system provided by this embodiment. The compressor oil recovery system of the air conditioning system includes an air conditioning system 100 and a refrigerant recovery filling machine 200. As shown in FIG. 1, the air conditioning system 100 generally includes a second compressor 101, a condenser 102, an expansion valve 103, and an evaporator 104 that are connected in sequence. The refrigerant recovery and filling machine 200 includes a first port and a second port, and the two ports of the refrigerant recovery and filling machine 200 are respectively connected to the air conditioning system 100. In one embodiment, the two ports of the refrigerant recovery filling machine 200 are respectively connected to the high-pressure side 107 and the low-pressure side 108 of the air conditioning system 100 (wherein the high-pressure side 107 of the air conditioning system 100 means that the air conditioning system 100 is in a normal working state. The side downstream of the outlet of the second compressor 101, and the low pressure side 108 of the air conditioning system 100 refers to the side upstream of the inlet of the second compressor 101 when the air conditioning system 100 is in a normal working state. The refrigerant recovery filling machine 200 is configured to fill the air conditioning system 100 with liquid refrigerant through the first port to dissolve the compressor oil of the air conditioning system 100, and to recover the refrigerant and the air conditioning system from the air conditioning system 100 through the second port 100 is a mixture of compressor oil; and, filling the air conditioning system 100 with liquid refrigerant through the second port to dissolve the compressor oil of the air conditioning system 100, and recovering it from the air conditioning system 100 through the first port A mixture of refrigerant and compressor oil. In addition, the refrigerant recovery and filling machine 200 is also configured to separate the compressor oil and refrigerant in the mixture and separately recover the compressor oil through the circulation of the refrigerant to dissolve the compressor oil, which can be used without removing any components of the air conditioning system 100 Under the premise, basically all the compressor oil in the air conditioning system 100 is recycled. In an embodiment, a known amount of compressor oil can also be injected into the air conditioning system 100 after the compressor oil is recovered, so as to help ensure the stable performance of the air conditioning system 100.

FIG. 2 is a schematic structural diagram of the internal structure of a refrigerant recovery filling machine 200 according to an embodiment. As shown in FIG. 2, the refrigerant recovery filling machine 200 includes a compressor oil separation device 201, a first compressor 202, a refrigerant storage tank 203 and a new compressor oil container 204. The compressor oil separation device 201, the first compressor 202, and the refrigerant storage tank 203 communicate in sequence. The compressor oil separation device 201 is configured to be a mixture of refrigerant and compressor oil recovered from the air conditioning system 100, and to separate the compressor oil from the mixture. The first compressor 202 is configured to provide power for recovering the mixture of refrigerant and compressor oil in the air conditioning system 100. In one embodiment, the refrigerant storage tank 203 is a sealed container, and the refrigerant storage tank 203 is configured to pre-store a liquid refrigerant for dissolving the compressor oil in the air conditioning system 100 before recovering the compressor oil to remove the liquid refrigerant Filled into the air conditioning system 100, the refrigerant storage tank 203 is also configured to store the refrigerant separated from the compressor oil separation device 201, and each inlet and outlet of the refrigerant storage tank 203 is optionally provided with a control valve. The new compressor oil container 204 is configured to supply the new compressor oil to the air conditioning system 100 after the compressor oil in the air conditioning system 100 is basically recovered. In one embodiment, a one-way valve 217 is provided between the first compressor 202 and the refrigerant recovery inlet 2032 of the refrigerant storage tank 203, so that the refrigerant can only flow from the first compressor 202 to the refrigerant storage tank 203 in one direction. . In one embodiment, in order to realize the start and stop, the two ports of the refrigerant recovery filling machine 200 are respectively communicated with the high pressure side 107 and the low pressure side 108 of the air conditioning system 100 through control valves. Each control valve in this article can be a solenoid valve. In the embodiment shown in FIG. 2, a control valve 210 communicating with the high-pressure side 107 of the air conditioning system 100 is provided at the inlet end of the refrigerant recovery filling machine 200 (that is, the end close to the inlet of the compressor oil separation device 201). The inlet end of the refrigerant recovery and filling machine 200 is also provided with a control valve 211 communicating with the low-pressure side 108 of the air conditioning system 100, and the liquid refrigerant outlet end of the refrigerant recovery and filling machine 200 (that is, near the liquid phase of the refrigerant storage tank 203) One end of the refrigerant outlet 2031) is provided with a control valve 212 communicating with the high-pressure side 107 of the air-conditioning system 100, and a control valve communicating with the low-pressure side 108 of the air-conditioning system 100 is also provided at the liquid refrigerant outlet end of the refrigerant recovery filling machine 200 Four 213. When the control valve one 210 and the control valve four 213 are opened, the liquid refrigerant in the refrigerant recovery filling machine 200 is injected into the air conditioning system 100 through the control valve four 213 through the low pressure side 108, and the liquid refrigerant injected into the air conditioning system 100 will After the compressor oil in the system 100 is dissolved, the mixture of the refrigerant and compressor oil in the air conditioning system 100 enters the refrigerant recovery filling machine 200 from the high pressure side 107 of the air conditioning system 100. When the control valve two 211 and the control valve three 212 are opened, the liquid refrigerant in the refrigerant recovery filling machine 200 is injected into the air conditioning system 100 through the control valve three 212 through the high pressure side 107, and the liquid refrigerant injected into the air conditioning system 100 will After the compressor oil in the system 100 is dissolved, the mixture of the refrigerant and the compressor oil in the air conditioning system 100 enters the refrigerant recovery filling machine 200 from the low pressure side 108 of the air conditioning system 100. By opening control valve one 210 and control valve four 213, or opening control valve two 211 and control valve three 212, the compressor oil in the air conditioning system 100 can be flushed and recovered from two different directions. The flushing effect of compressor oil Better and higher recycling efficiency.

It should be noted that in other embodiments, a four-way valve can also be used to replace the four control valves from control valve one 210 to control valve four 213, which can realize the two ends of the refrigerant recovery filling machine 200 and the air conditioning system 100. The two ports (ie, the high-pressure side 107 and the low-pressure side 108) can be connected correspondingly. It should be noted that, in specific implementation, the communication relationship between the two ports of the refrigerant recovery filling machine 200 and the high-pressure side 107 and the low-pressure side 108 of the air conditioning system 100 can also be exchanged, for example, the refrigerant recovery The inlet end of the injection machine 200 communicates with the high-pressure side 107 of the air conditioning system 100 through a control valve, and the liquid refrigerant outlet end of the refrigerant recovery filling machine 200 communicates with the low-pressure side 108 through a control valve; or the inlet of the refrigerant recovery filling machine 200 The end is communicated with the low pressure side 108 of the air conditioning system 100 through a control valve, and the liquid refrigerant outlet end of the refrigerant recovery filling machine 200 is communicated with the high pressure side 107 through a control valve. In this embodiment, there is only one direction for flushing and recovering the compressor oil in the air conditioning system 100. It should be noted that, as shown in Figures 1 and 2, in order to facilitate the separate operation of the refrigerant recovery filling machine 200 and the air conditioning system 100, both ends of the air conditioning system 100 may be provided with a control valve 105 and a control valve 10 respectively. Two 106, control valve eleven 105 and control valve twelve 106 may be needle valves. When the two ends of the air conditioning system 100 are provided with control valve eleven 105 and control valve twelve 106, control valve one 210 to control valve four 213 may be set or not provided as needed.

In the embodiment shown in FIG. 2, the refrigerant recovery filling machine 200 further includes a vacuum pump 209, and the vacuum pump 209 communicates with the air conditioning system 100 through a control valve 13 216. The vacuum pump 209 is configured to perform a vacuum operation on the air conditioning system 100 before injecting new compressor oil into the air conditioning system 100. The new compressor oil container 204 is also set to communicate with the air conditioning system 100 through the control valve 215 for easy control. In the embodiment shown in FIG. 2, the bottom of the new compressor oil container 204 is connected with a new oil weighing sensor 205, and the new oil weighing sensor 205 can be used to calculate the new compressor oil container 204. The compressor oil quality controls the amount of oil supplied by the new compressor oil container 204 to the air conditioning system 100. In the embodiment shown in FIG. 2, the bottom of the refrigerant storage tank 203 is connected with a refrigerant weighing sensor 206, and the quality of the refrigerant in the refrigerant storage tank 203 can be calculated from the measurement result of the refrigerant weighing sensor 206. For different air conditioning systems 100, the minimum amount of refrigerant that needs to be stored in advance in the refrigerant storage tank 203 is different. In one embodiment, the minimum amount of refrigerant that needs to be stored in the refrigerant storage tank 203 can be set according to the initial compressor oil amount in the air conditioning system 100, and the refrigerant load cell 206 can be used before the compressor oil is recovered. To determine whether the amount of refrigerant in the refrigerant storage tank 203 is higher than the minimum amount of refrigerant that needs to be stored in advance. As shown in FIG. 2, a pressure sensor 207 can also be provided between the inlet of the first compressor 202 and the air conditioning system 100 to measure the pressure in the refrigerant recovery filling machine 200. The pressure sensor 207 can optionally be arranged between the control valve one 210, the control valve two 211 and the inlet of the compressor oil separation device 201. When the control valve one 210 or the control valve two 211 is opened, the pressure sensor 207 can measure the pressure in the air conditioning system 100, and when the opened control valve one 210 or the control valve two 211 is closed, the pressure sensor 207 can only measure the refrigerant recovery The pressure in the filling machine 200 upstream of the first compressor 202. It is understandable that the number of pressure sensors can be multiple, and the location of the pressure sensor can be specifically set according to the location where the pressure needs to be measured. In an embodiment, a high-pressure switch 208 may be provided at the outlet of the first compressor 202. The high-pressure switch 208 monitors the pressure at the outlet of the first compressor 202. When a high pressure is detected, the high-pressure switch 208 is activated and opened, thereby The recovery process is suspended to ensure the safety of the refrigerant recovery filling machine 200.

FIG. 3 is a schematic structural diagram of a compressor oil separation device 201 according to an embodiment of this document. Please refer to FIGS. 2 and 3 in combination. In one embodiment, the compressor oil separation device 201 includes an oil and gas separator 2011, a buffer container 2012, and an old oil container 2013. Both the oil and gas separator 2011 and the buffer container 2012 are sealed containers. The oil and gas separator 2011 has an inlet 20111, a gaseous refrigerant inlet 20112, a refrigerant outlet 20113, and an oil outlet 20114. The buffer container 2012 has an oil inlet and an oil outlet. The inlet 20111, the gas refrigerant inlet 20112, and the refrigerant outlet 20113 of the oil-air separator 2011 are all optionally arranged at the top of the oil-gas separator 2011, and the oil outlet 20114 of the oil-gas separator 2011 is optionally arranged at the bottom of the oil-gas separator 2011, The oil outlet 20114 of the oil and gas separator 2011 is arranged at the bottom of the oil and gas separator 2011 to facilitate the complete discharge of the compressor oil that drops to the bottom of the oil and gas separator 2011. The refrigerant outlet 20113 of the oil-air separator 2011 is in communication with the inlet of the first compressor 202. The oil outlet 20114 of the oil-air separator 2011 communicates with the oil inlet of the buffer container 2012 through the control valve five 2014, and the oil outlet of the buffer container 2012 communicates with the old oil container 2013 through the control valve six 2015. The inlet 20111 of the oil-gas separator 2011 is provided with a control valve seven 2016, and the refrigerant outlet 20113 of the oil-gas separator 2011 is provided with a control valve eight 2017. The gaseous refrigerant outlet of the refrigerant storage tank 203 is connected to the gaseous refrigerant inlet 20112 through the control valve 9214, so that the gaseous refrigerant can be injected into the oil-gas separator 2011 when necessary to increase the pressure in the oil-gas separator 2011 and then the oil-gas separator 2011 The compressor oil is discharged. Control valve nine 214 can optionally be opened intermittently. It should be noted that, in order to simplify the structure, the gaseous refrigerant outlet of the refrigerant storage tank 203 in this specific embodiment and the refrigerant recovery inlet 2032 of the refrigerant storage tank 203 in FIG. 2 are the same opening. Of course, in other embodiments, the gaseous refrigerant outlet of the refrigerant storage tank 203 and the refrigerant recovery inlet 2032 of the refrigerant storage tank 203 may be set to different openings. The gaseous refrigerant outlet and the refrigerant recovery inlet 2032 of the refrigerant storage tank 203 can be arranged on the top of the refrigerant storage tank 203, so that the vaporized refrigerant vapor in the refrigerant storage tank 203 directly enters the oil and gas separator 2011 through the gaseous refrigerant outlet and pipeline Gaseous refrigerant is imported in 20112. In one embodiment, the liquid refrigerant outlet 2031 of the refrigerant storage tank 203 communicates with a pipeline extending to the bottom of the refrigerant storage tank 203, so that the pipeline extending to the bottom of the refrigerant storage tank 203 is connected to the air conditioning system 100 through the liquid refrigerant outlet 2031. Connected. It should be noted that by providing the control valve seven 2016 and the control valve eight 2017, it is possible to prevent the refrigerant recovered in the refrigerant storage tank 203 from entering other pipelines when the compressor oil is discharged, thereby improving the recovery rate of refrigerant. In other embodiments, at least one of the control valve seven 2016 and the control valve eight 2017 may not be provided. It should be noted that the buffer container 2012 can temporarily buffer the compressor oil before the compressor oil is discharged to the old oil container 2013. When the control valve between the buffer container 2012 and the oil and gas separator 2011 is opened, the oil and gas separator 2011 can pass the refrigerant The negative pressure in the recycling filling machine 200 recovers the refrigerant carried in the buffer container 2012 to minimize the loss of refrigerant. In other embodiments, the cache container 2012 may not be provided.

FIG. 4 is a schematic structural block diagram of the control system 300 of the refrigerant recovery filling machine 200 according to an embodiment of this document. As shown in Figure 4, the control system 300 includes a controller 301. The controller 301 can be a microprocessor. The controller 301 can receive and read from the pressure sensor 207, the high pressure switch 208, the fresh oil weighing sensor 205 and the refrigerant weighing The signal of at least one of the sensors 206 and can send a signal to open or close at least one of each control valve, the first compressor 202 and the vacuum pump 209. The control system 300 may also be connected with a display device 302 and an input device 303 to realize human-computer interaction.

This article also provides a compressor oil recovery method for an air conditioning system, which can be implemented for the compressor oil recovery system based on the above air conditioning system. The method includes adding liquid refrigerant to the air conditioning system 100 to dissolve the compressor oil in the air conditioning system 100, and recovering the mixture of the compressor oil and the refrigerant from the air conditioning system 100. This method can circulate the refrigerant in the air conditioning system 100 and the refrigerant recovery filling machine 200, and separate the compressor oil and refrigerant mixture recovered from the air conditioning system 100. This method uses a certain amount of refrigerant to dissolve the compressor oil in the air-conditioning system 100 and recover the mixture of refrigerant and compressor oil, which can realize the compressor in the air-conditioning system 100 without removing any components of the air-conditioning system 100. Almost all the oil is recycled. In one embodiment, after substantially all of the compressor oil in the air conditioning system 100 is recovered, a known amount of new compressor oil can also be injected into the air conditioning system 100, so as to help ensure stable performance of the air conditioning system.

In the embodiment shown in FIG. 5, the compressor oil recovery method of the air conditioning system 100 includes the following steps.

In step A: the control system 300 is initialized.

In step B: Cycle 1 and Cycle 2 are performed alternately. Cycle 1 fills the air conditioning system 100 with liquid refrigerant from the low pressure side 108 of the second compressor 101 of the air conditioning system 100, and recovers the mixture of refrigerant and compressor oil from the high pressure side 107 of the air conditioning system 100. Cycle 2 fills the air conditioning system 100 with liquid refrigerant from the high pressure side 107 of the second compressor 101 of the air conditioning system 100, and recovers the mixture of refrigerant and compressor oil from the low pressure side 108 of the air conditioning system 100. The execution order of loop 1 and loop 2 is not limited, that is, loop 1 or loop 2 can be performed first. In the following, we will take cycle 1 first as an example. Loop 1 and Loop 2 are executed continuously at least once. In this embodiment, loop 1 and loop 2 are executed three consecutive times as an example. In one embodiment, the number of times the cycle 1 and the cycle 2 are executed is calculated by the number of times the oil-air separator 2011 drains oil outward, and once the oil is drained outward, the cycle is executed once. In addition, in this embodiment, the priority of the refrigerant cycle time may be higher than the priority of the cycle number of cycles 1 and 2, that is, whether the recovery of compressor oil is completed is subject to the preset time of the refrigerant cycle.

In step C: recover all refrigerant and process compressor oil.

In an embodiment, as shown in FIG. 6, the above step A may include the following steps.

In step A1, the refrigerant circulation time T is set. Because air conditioning systems 100 of different automobile manufacturers and models have different capacities, the refrigerant cycle time T required to recover all compressor oil from different air conditioning systems 100 is different. This time T is set according to the specific conditions of the air conditioning system 100. set.

In step A2, time variables t1, t2, and the number of oil separation times n1 and n2 are set. t1 is the current actual refrigerant cycle time, the initial value of t1 is set to zero and t1 increases with time, so that the total cycle time of the recovery and separation of compressor oil can be controlled by comparing t1 and T. t2 is the actual execution time of a certain cycle 1 or cycle 2. The initial value of t2 is set to zero and t2 increases with the execution time of a certain cycle 1 or cycle 2, so as to control the compressor oil from the oil and gas separator 2011 The refrigerant is circulated for a preset time before discharge. In this embodiment, 90s is taken as an example for introduction. n1 is the number of continuous execution of loop 1, and n2 is the number of continuous execution of loop 2. n1 and n2 can be equal or unequal. In this embodiment, both n1 and n2 are 3 as an example. During the recovery process, the initial value of n1 and n2 is zero, n1 gradually increases with the number of continuous executions of loop 1, and n2 gradually increases with the number of continuous executions of loop 2. When n1 or n2 reaches the set value, the corresponding end The loop 1 or loop 2.

In step A3, the controller 301 reads the detection results of the refrigerant weighing sensor 206 and the high-voltage switch 208 to determine whether the operation can be continued, if the operation is continued, proceed to step B, and if the operation is not continued, it can prompt for manual processing. For example, if the high voltage switch 208 is opened due to the detection of high voltage, the operation is not continued and manual processing is prompted. For another example, if the detection result of the refrigerant load cell 206 (that is, the weight of the refrigerant) is greater than the maximum allowable weight of the refrigerant stored in the refrigerant storage tank 203, or the detection result of the refrigerant load cell 206 is less than the equipment required to recover the compressor oil If the minimum amount of refrigerant is set, the operation will not be continued and manual processing will be prompted.

Step B may include the following steps.

In step B10, the refrigerant performs a preset cycle 1 between the refrigerant recovery filling machine 200 and the air conditioning system 100. In this embodiment, the cycle 1 is performed three times, and then the refrigerant changes its flow direction, and step B20 is performed.

In step B20, the refrigerant performs a preset second cycle 2 between the refrigerant recovery filling machine 200 and the air conditioning system 100, and in this embodiment, three cycles 2 are performed.

Step B10 includes the following steps.

In step B11, control valve one 210, control valve four 213, control valve seven 2016, and control valve eight 2017 are opened, and the remaining valves are closed to connect the two ports of the refrigerant recovery filling machine 200 to the air conditioning system 100 respectively (This makes one of the two ports of the refrigerant recovery and filling machine 200 communicate with the high-pressure side 107 of the air conditioning system 100, and the other of the two ports of the refrigerant recovery and filling machine 200 is connected to the air conditioner The low pressure side 108 of the system 100 is connected), the first compressor 202 is turned on for t2=90s, liquid refrigerant is added to the low pressure side 108 of the air conditioning system 100, and the mixture of refrigerant and compressor oil is recovered from the high pressure side 107 of the air conditioning system 100 . Specifically, the mixture is separated in the oil-gas separator 2011, the compressor oil drops to the bottom of the oil-gas separator 2011, and part of the separated refrigerant is stored in the refrigerant storage tank 203 after passing through the first compressor 202.

In step B121, control valve one 210 and control valve four 213 are closed, and the first compressor 202 is kept open until the pressure upstream of the first compressor 202 reaches the first preset value (the value measured by the pressure sensor 207 is the first The pressure value upstream of the compressor 202). In this embodiment, the first preset value is 0 bar to recover the refrigerant from the oil-air separator 2011.

In step B122, the control valve five 2014 is opened, while the first compressor 202 is kept on until the pressure upstream of the first compressor 202 reaches a second preset value, the second preset value can be selected to be less than the first preset value, In this embodiment, the second preset value is ≦-0.5 bar to recover the refrigerant in the buffer container 2012 and minimize the loss of refrigerant.

In step B13, the first compressor 202 is closed, the control valve seven 2016 and the control valve eight 2017 are closed, the control valve five 2014 is kept open, and the control valve nine 214 is opened for a preset time, such as 10 seconds. The control valve nine 214 is optional In order to be opened intermittently to discharge the compressor oil in the lower part of the oil and gas separator 2011 into the buffer tank 2012, the control valve 5 2014 is closed after the compressor oil in the oil and gas separator 2011 is discharged.

In step B121 and step B122, make the pressure value upstream of the compressor reach 0 bar or below. On the one hand, it is to recover the refrigerant, and on the other hand, it is to make the gaseous refrigerant in the refrigerant storage tank 203 under negative pressure in step B13. Under the action, it enters the oil and gas separator 2011 to pressurize the oil and gas separator 2011 to discharge the compressor oil in the oil and gas separator 2011.

In step B14, compare variables t1 and T, if t1≧T, go to step C, otherwise go to step B15.

In step B15, the variable oil separation times n1 is increased by 1, and the variable n1 is compared with the value 3. If n1=3, then n1 and t2 are returned to zero and step B20 is performed, specifically, B21 is performed, that is, loop 2 is performed, otherwise t2 is reset to zero and step B11 is performed.

Wherein step B20 includes the following steps:

In step B21, control valve two 211, control valve three 212, control valve seven 2016, and control valve eight 2017 are opened, and the remaining valves are closed to connect the two ports of the refrigerant recovery filling machine 200 to the air conditioning system 100 respectively (This makes one of the two ports of the refrigerant recovery and filling machine 200 communicate with the high-pressure side 107 of the air conditioning system 100, and the other of the two ports of the refrigerant recovery and filling machine 200 is connected to the air conditioner The low-pressure side 108 of the system 100 is connected), the first compressor 202 is started for t2=90s, the air-conditioning system 100 is filled with liquid refrigerant through the high-pressure side 107 of the air-conditioning system 100, and the refrigerant and refrigerant are recovered from the low-pressure side 108 of the air conditioning system 100 The mixture of compressor oil is separated in the oil and gas separator 2011, and the compressor oil drops to the bottom of the oil and gas separator 2011, and the separated refrigerant is stored in the refrigerant storage tank 203 of the refrigerant recovery filling machine 200, thereby realizing the The flow of cycle 2 flows.

In step B221, the control valve two 211 and the control valve three 212 are closed, and the first compressor 202 is kept open until the pressure upstream of the first compressor 202 reaches a first preset value. In this embodiment, the preset value is 0 bar. To recover refrigerant from the oil and gas separator 2011.

In step B222, the control valve 5 2014 is opened, while the first compressor 202 is kept on until the pressure upstream of the first compressor 202 reaches a second preset value, the second preset value can be selected to be less than the first preset value, In this embodiment, the second preset value is ≦-0.5 bar to recover the refrigerant in the buffer container 2012.

In step B23, the first compressor 202 is closed, the control valve seven 2016 and the control valve eight 2017 are closed, the control valve five 2014 is kept open, and the control valve nine 214 is opened for a preset time, such as 10 seconds. The control valve nine 214 is optional To open it intermittently to discharge the compressor oil in the lower part of the oil-gas separator 2011 into the buffer container 2012, the control valve 5 2014 is closed after the compressor oil in the oil-gas separator 2011 is discharged.

In step B24, compare variables t1 and T, if t1≧T, go to step C, otherwise go to step B25.

In step B25, the variable oil separation times n2 is increased by 1, and the variable n2 is compared with the value 3. If n2=3, then n2 and t2 are reset to zero and step B10 is performed, specifically, B11 is performed, that is, loop 1 is performed, otherwise t2 returns to zero and proceeds to step B21.

Step C includes the following steps.

In step C1, close control valve three 212 and control valve four 213, open control valve one 210, control valve two 211, control valve seven 2016, control valve eight 2017, and turn on the first compressor 202 to the upstream of the first compressor 202 The pressure reaches the third preset value. In this embodiment, the third preset value may be equal to the first preset value, and the third preset value in this embodiment is 0 bar;

In step C2, keep the first compressor 202 turned on, and open the control valve 2014 until the pressure upstream of the first compressor 202 reaches a fourth preset value, which may be equal to or less than the third preset value, In this embodiment, the fourth preset value≦-0.5bar;

In step C3, the first compressor 202 is closed, the control valve one 210, the control valve two 211, the control valve seven 2016 and the control valve eight 2017 are closed, the control valve five 2014 is kept open, the control valve six 2015 is opened, and the control valve nine is opened 214 For a preset time, such as 10 seconds, the control valve 9 214 can be selected to be opened intermittently to inject the gaseous refrigerant in the refrigerant storage tank 203 into the oil-air separator 2011 to remove the compressor oil in the lower part of the oil-air separator 2011 and The compressor oil in the buffer tank 2012 is discharged into the used oil tank 2013.

Then the whole process ends.

It should be noted that, in other embodiments, if the control valve seven 2016 and the control valve eight 2017 are not provided at the inlet 20111 and the refrigerant outlet 20113 of the oil-air separator 2011, the above is related to the control valve seven 2016 and the control valve eight 2017 In the step, the opening and closing operations of the control valve seven 2016 and the control valve eight 2017 can be omitted. In addition, it is judged whether it is necessary to open other control valves between the inlet of the oil and gas separator, the outlet of the refrigerant and the air conditioning system based on whether it is necessary to connect the oil and gas separator with the air conditioning system. For example, when the compressor oil is discharged from the oil and gas separator 2011, if the control valve seven 2016 and the control valve eight 2017 are not set, the control valve between the inlet end of the refrigerant recovery filling machine 200 and the air conditioning system 100 can be closed One 210, control valve two 211, and control valve three 212 and control valve four 213 between the outlet end of the refrigerant recovery filling machine 200 and the air conditioning system 100, and then the refrigerant storage tank 203 injects gaseous refrigerant into the oil and gas separator 2011. Drain. For another example, in steps B13 and B23, the control valve seven 2016 and the control valve eight 2017 can be changed to close the control valve 210 and the control valve 210 between the inlet end of the refrigerant recovery filling machine 200 and the air conditioning system 100. Two 211, and the control valve three 212 and control valve four 213 between the outlet end of the refrigerant recovery filling machine 200 and the air conditioning system 100, but after the modification, the refrigerant enters outside the oil and gas separator 2011 when the oil and gas separator 2011 is draining oil In the pipeline. Therefore, comparatively speaking, by setting the control valve seven 2016 and the control valve eight 2017, it is beneficial to increase the recovery rate of the refrigerant.

It should be noted that in other embodiments, only loop 1 or only loop 2 may be performed. The number of executions of loop 1 and loop 2 is not limited and can be selected as at least twice. However, considering the recovery efficiency and time cost, it is optional For the loop 3-6 times. For example, the two ends of the refrigerant recovery filling machine 200 are respectively connected to one side of the air conditioning system 100 through a control valve, then when only the operation from step B11 to step B15 or only the operation from step B22 to step B25 is performed, the refrigerant is turned on The corresponding control valve at the inlet end and/or outlet end of the filling machine 200 can be recovered.

The compressor oil recovery method of the air-conditioning system described above can predetermine the number of refrigerant circulation and oil draining within a preset processing time, so as to recover all compressor oil and refrigerant from the air-conditioning system.

In one embodiment, the compressor oil recovery method of the air-conditioning system includes at least one of the following: injecting liquid refrigerant into the air-conditioning system 100 from a first direction to dissolve the compressor oil of the air-conditioning system 100; The system 100 recovers the mixture of refrigerant and compressor oil; and injects liquid refrigerant into the air conditioning system 100 from the second direction to dissolve the compressor oil of the air conditioning system 100, and recovers the refrigerant from the air conditioning system 100 from the first direction Mixture with compressor oil.

In one embodiment, the liquid refrigerant is added to the air conditioning system 100 from the first direction to dissolve the compressor oil of the air conditioning system 100, and the mixture of refrigerant and compressor oil is recovered from the air conditioning system 100 from the second direction as cycle 1. The cycle 1 includes: injecting the liquid refrigerant into the low pressure side 108 of the air conditioning system 100, and recovering the mixture of the refrigerant and compressor oil from the high pressure side 107 of the air conditioning system 100.

In an embodiment, the liquid refrigerant is added to the air conditioning system 100 from the second direction to dissolve the compressor oil of the air conditioning system 100, and the refrigerant and compressor oil are recovered from the air conditioning system 100 from the first direction. The mixture is cycle 2, which includes: injecting the liquid refrigerant into the high pressure side 107 of the air conditioning system 100, and recovering the mixture of the refrigerant and compressor oil from the low pressure side 108 of the air conditioning system 100.

In one embodiment, the liquid refrigerant is added to the air conditioning system 100 from the first direction to dissolve the compressor oil of the air conditioning system 100, and the mixture of refrigerant and compressor oil is recovered from the air conditioning system 100 from the second direction as cycle 1. The liquid refrigerant is added to the air-conditioning system 100 from the second direction to dissolve the compressor oil of the air-conditioning system 100, and the mixture of refrigerant and compressor oil is recovered from the air-conditioning system 100 from the first direction as cycle 2;

The compressor oil recovery method of the air conditioning system is implemented based on a refrigerant recovery and filling machine, which includes an oil-gas separator 2011, a first compressor 202, and a refrigerant storage tank 203 that are connected in sequence; the cycle 1 and The cycle 2 includes the following steps:

The two ports of the refrigerant recovery filling machine 200 are respectively connected to the high pressure side 107 and the low pressure side 108 of the air conditioning system 100, and one port of the refrigerant recovery filling machine 200 is used to fill the air conditioning system 100 with liquid refrigerant. The other port of the injection machine 200 recovers the compressor oil and refrigerant mixture from the air conditioning system 100, and separates the refrigerant and the compressor oil in the oil and gas separator 201.

In one embodiment, the two ports of the refrigerant recovery filling machine 200 are respectively connected to the high pressure side 107 and the low pressure side 108 of the air conditioning system 100, and one port of the refrigerant recovery filling machine 200 is connected to the air conditioning system 100. Fill the liquid refrigerant, recover the compressor oil and refrigerant mixture from the air conditioning system 100 through the other port of the refrigerant recovery filling machine 200, and separate the refrigerant and the compressor oil in the oil-air separator 201, then cycle 1 and cycle 2 It also includes the following steps:

Close the control valve one 210, control valve two 211, control valve three 212 and control valve four 213 between the two ports of the refrigerant recovery filling machine 200 and the air conditioning system 100, and turn on the first compressor 202 Until the pressure upstream of the first compressor 202 reaches the first preset value;

Turn off the first compressor 202, close the control valve seven 2016 between the inlet 20111 of the oil and gas separator 2011 and the air conditioning system 100, and open the control valve five at the oil outlet 20114 of the oil and gas separator 2011. In 2014, the control valve 9214 between the gaseous refrigerant outlet of the refrigerant storage tank 203 and the gaseous refrigerant inlet 20112 of the oil-gas separator 2011 is opened to inject the gaseous refrigerant in the refrigerant storage tank 203 into the oil-gas separator The compressor 2011 is pressurized to discharge the compressor oil in the lower part of the oil-air separator 2011.

In an embodiment, the refrigerant recovery and filling machine 200 further includes a buffer container 2012, and the buffer container 2012 is in communication with the oil outlet 20114 of the oil-gas separator 2011 through a control valve five 2014;

When the two ports of the refrigerant recovery and filling machine 200 are respectively connected to the high-pressure side 107 and the low-pressure side 108 of the air conditioning system 100, one port of the refrigerant recovery and filling machine 200 is used to fill the air conditioning system 100 with liquid refrigerant. The other port of the refrigerant recovery filling machine 200 recovers the compressor oil and refrigerant mixture from the air conditioning system 100, and after the refrigerant and compressor oil are separated in the oil-air separator 201, both cycle 1 and cycle 2 further include the following steps:

Open the control valve 2014 between the oil outlet 20114 of the oil-air separator 2011 and the buffer container 2012, and keep the first compressor 202 open until the pressure upstream of the first compressor 202 reaches the second preset Set value

In an embodiment, after the compressor oil recovery method of the air conditioning system executes at least one of the cycle 1 and the cycle 2, the method further includes the following steps:

Close the control valve three 212 and control valve four 213 between the liquid refrigerant outlet end of the refrigerant recovery filling machine 200 and the air conditioning system 100, and open the inlet 20111 of the oil-air separator 2011 and the air conditioning system 100 The control valve number seven 2016 between the time and the first compressor 202 is turned on until the pressure upstream of the first compressor 202 reaches the third preset value;

Turn off the first compressor 202, close the control valve seven 2016 between the inlet 20111 of the oil and gas separator 2011 and the air conditioning system 100, and open the control valve five at the oil outlet 20114 of the oil and gas separator 2011. In 2014, open the control valve 2015 between the oil outlet 20114 of the buffer container 2012 and the old oil container 2013, and open the gap between the gas refrigerant outlet of the refrigerant storage tank 203 and the gas refrigerant inlet 20112 of the oil-air separator 2011 The control valve 9214 injects the gaseous refrigerant in the refrigerant storage tank 203 into the oil and gas separator 2011 to discharge the compressor oil in the lower part of the oil and gas separator 2011 and the compressor oil in the buffer tank 2012 to old oil Container 2013.

The compressor oil recovery system and method of the air conditioning system provided in this article can add liquid refrigerant to the air conditioning system to dissolve the compressor oil, and recover and separate the mixture of refrigerant and compressor oil from the air conditioning system through multiple cycles of refrigerant Dissolve, it can recover almost all the compressor oil in the air conditioning system for processing without removing any parts of the air conditioning system, or inject a known amount of compressor oil into the air conditioning system after the compressor oil is recovered; Moreover, the gaseous refrigerant in the refrigerant storage tank can be used to pressurize the oil and gas separator to discharge the compressor oil in the oil and gas separator; in addition, a buffer container is set up in this article to regularly discharge the compressor oil into the buffer container and the next time The refrigerant in the buffer container is further recovered before draining the oil into the buffer container, and the loss of refrigerant is small; in addition, this article washes and recovers the compressor oil in the air conditioning system from two directions. The compressor oil has a better washing effect and a more efficient recovery. high.

FIG. 11 is a schematic diagram of the hardware structure of an electronic device provided by an embodiment of this document. The electronic device shown in FIG. 11, the control system or controller shown in FIG. 4 may be specifically configured as the electronic device shown in FIG. 11 . The electronic device in FIG. 11 includes: one or more processors 310 and a memory 320. A processor 310 is taken as an example in FIG. 11.

The electronic device may further include: an input device 303 and an output device 330.

The processor 310, the memory 320, the input device 303, and the output device 330 in the electronic device may be connected by a bus or other methods. In FIG. 11, a bus connection is taken as an example.

The memory 320, as a computer-readable storage medium, can be configured to store software programs, computer-executable programs, and modules. The processor 310 executes various functional applications and data processing by running software programs, instructions, and modules stored in the memory 320 to implement any one of the methods in the foregoing embodiments.

The memory 320 may include a program storage area and a data storage area. The program storage area may store an operating system and an application program required by at least one function; the data storage area may store data created according to the use of the electronic device, and the like. In addition, the memory may include volatile memory such as random access memory (RAM), and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-transitory solid state storage device.

The memory 320 may be a non-transitory computer storage medium or a transitory computer storage medium. The non-transitory computer storage medium, for example, at least one magnetic disk storage device, flash memory device, or other non-volatile solid state storage device. In some embodiments, the memory 320 may optionally include a memory remotely provided with respect to the processor 310, and these remote memories may be connected to the electronic device through a network. Examples of the aforementioned network may include the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

The input device 303 may be configured to receive inputted number or character information, and generate key signal input related to user settings and function control of the electronic device. The output device 330 may include a display device such as a display screen.

This embodiment also provides a computer-readable storage medium storing computer-executable instructions configured to execute the above-mentioned method.

All or part of the processes in the methods of the above-mentioned embodiments can be implemented by a computer program that executes related hardware. The program can be stored in a non-transitory computer-readable storage medium. When the program is executed, it can include the methods described above. In the process of the embodiment of, the non-transitory computer-readable storage medium may be a magnetic disk, an optical disk, a read-only memory (Read-Only Memory, ROM), or RAM, etc.

Claims

A refrigerant recovery and filling machine, comprising: a first port and a second port; wherein the refrigerant recovery and filling machine (200) is configured to be at least one of the following: to an air conditioning system (100) through the first port Filling a liquid refrigerant to dissolve the compressor oil of the air conditioning system (100), and recovering the mixture of refrigerant and compressor oil from the air conditioning system (100) through the second port; and, through the second port The air conditioning system (100) is filled with liquid refrigerant to dissolve the compressor oil of the air conditioning system (100), and the mixture of the refrigerant and the compressor oil is recovered from the air conditioning system (100) through the first port.
The refrigerant recovery filling machine according to claim 1, wherein the two ports of the refrigerant recovery filling machine (200) are connected to the high pressure side (107) and low pressure side of the air conditioning system (100) through a control valve, respectively (108) Connected.
The refrigerant recovery filling machine according to claim 1 or 2, wherein the first port of the refrigerant recovery filling machine (200) passes through the control valve one (210) and the high pressure side (100) of the air conditioning system (100). 107) Connect;

The first port of the refrigerant recovery filling machine (200) communicates with the low pressure side (108) of the air conditioning system (100) through the second control valve (211);

The second port of the refrigerant recovery filling machine (200) communicates with the high pressure side (107) of the air conditioning system (100) through the control valve three (212);

The second port of the refrigerant recovery filling machine (200) communicates with the low pressure side (108) of the air conditioning system (100) through a control valve four (213).
The refrigerant recovery and filling machine according to any one of claims 1-3, further comprising sequentially connected:

A compressor oil separation device (201), configured to recover a mixture of refrigerant and compressor oil from the air conditioning system (100), and separate compressor oil from the mixture;

The first compressor (202), the first compressor (202) has an inlet and an outlet, and the first compressor (202) is configured to recover refrigerant and compressor oil in the air conditioning system (100) The mixture provides power; and

The refrigerant storage tank (203), the refrigerant storage tank (203) has a refrigerant recovery inlet (2032) and a liquid refrigerant outlet (2031), the refrigerant recovery inlet (2032) of the refrigerant storage tank (203) and the first The outlet of the compressor (202) is in communication, and the liquid refrigerant outlet (2031) of the refrigerant storage tank (203) is in communication with the air conditioning system (100), and is configured to be pre-stored for dissolving the air conditioning system (100) The liquid refrigerant in the compressor oil is used to fill the liquid refrigerant into the air conditioning system (100), and the refrigerant separated from the compressor oil separation device (201) is stored.
The refrigerant recovery filling machine according to claim 4, wherein the compressor oil separation device (201) comprises: an oil and gas separator (2011);

The oil and gas separator includes an inlet (20111), a refrigerant outlet (20113), and an oil outlet (20114); the inlet (20111) of the oil and gas separator is configured to communicate with the air conditioning system (100) to receive The mixture of refrigerant and compressor oil is recovered in the air conditioning system (100); the refrigerant outlet (20113) of the oil-air separator (2011) is connected to the inlet of the first compressor (202); the outlet of the oil-air separator The oil port (20114) is configured to discharge compressor oil separated from the mixture.
The refrigerant recovery and filling machine according to claim 5, the oil-gas separator (201) further comprises a gaseous refrigerant inlet (20112), and the gaseous refrigerant inlet (20112) of the oil-gas separator (201) is passed through a control valve 9 (214) is connected with the gaseous refrigerant outlet of the refrigerant storage tank (203).
The refrigerant recovery and filling machine according to claim 5, a control valve seven (2016) is provided at the inlet (20111) of the oil and gas separator (2011), and the refrigerant outlet (20113) of the oil and gas separator (2011) A control valve eight (2017) is provided at the location, and a control valve five (2014) is provided at the oil outlet (20114) of the oil-gas separator (2011).
According to the refrigerant recovery filling machine according to any one of claims 5-7, the compressor oil separation device 201 further comprises:

A buffer container (2012), the buffer container (2012) is in communication with the oil outlet (20114) of the oil-air separator (2011) through the control valve five (2014); and

An old oil container (2013), the old oil container (2013) communicates with the oil outlet of the buffer container (2012) through a control valve six (2015).
The refrigerant recovery and filling machine according to any one of claims 1-8, wherein the refrigerant recovery and filling machine is further provided with a vacuum pump (209), and the vacuum pump (209) is configured to pass through a control valve 13 (216) It is connected to the air-conditioning system (100) to vacuum the air-conditioning system (100) before injecting new compressor oil into the air-conditioning system (100).
A compressor oil recovery system for an air conditioning system, including:

Air conditioning system (100); and

A refrigerant recovery and filling machine (200), the refrigerant recovery and filling machine (200) is the refrigerant recovery and filling machine (200) according to any one of claims 1 to 9, and the refrigerant recovery and filling machine (200) The two ports of) are respectively communicated with the air conditioning system (100) through control valves.
A method for recovering compressor oil of an air conditioning system, the method comprising at least one of the following: injecting liquid refrigerant into an air conditioning system (100) from a first direction to dissolve the compressor oil of the air conditioning system (100), and from a second direction Recover the mixture of refrigerant and compressor oil from the air conditioning system (100); and inject liquid refrigerant into the air conditioning system (100) from the second direction to dissolve the compressor oil of the air conditioning system (100), from the first The direction recovers the mixture of refrigerant and compressor oil from the air conditioning system (100).
The method according to claim 11, wherein the liquid refrigerant is added to the air conditioning system (100) from the first direction to dissolve the compressor oil of the air conditioning system (100), and from the second direction from the air conditioning system (100) The mixture of recovered refrigerant and compressor oil is cycle 1, which includes: injecting the liquid refrigerant into the low pressure side (108) of the air conditioning system (100), and recovering the liquid refrigerant from the high pressure side (107) of the air conditioning system (100) The mixture of refrigerant and compressor oil.
The method according to claim 11, wherein the liquid refrigerant is added to the air conditioning system (100) from the second direction to dissolve the compressor oil of the air conditioning system (100), and the air conditioning system (100) is charged from the air conditioning system from the first direction. The mixture of recovered refrigerant and compressor oil in (100) is cycle 2. The cycle 2 includes: injecting the liquid refrigerant into the high pressure side (107) of the air conditioning system (100), from the low pressure side (100) of the air conditioning system (100) 108) Recover the mixture of the refrigerant and compressor oil.
The method according to any one of claims 11 to 13, wherein the liquid refrigerant is added to the air conditioning system (100) from the first direction to dissolve the compressor oil of the air conditioning system (100), and from the second direction The mixture of refrigerant and compressor oil recovered in the system (100) is cycle 1; the liquid refrigerant is added to the air-conditioning system (100) from the second direction to dissolve the compressor oil of the air-conditioning system (100). In the first direction, the mixture of refrigerant and compressor oil is recovered from the air conditioning system (100) as cycle 2;

The compressor oil recovery method of the air conditioning system is implemented based on a refrigerant recovery and filling machine, which includes an oil-gas separator (2011), a first compressor (202), and a refrigerant storage tank (203) connected in sequence ; The cycle 1 and the cycle 2 both include the following steps:

The two ports of the refrigerant recovery and filling machine (200) are respectively connected with the high pressure side (107) and the low pressure side (108) of the air conditioning system (100), and one port of the refrigerant recovery filling machine (200) is connected to the air conditioning system (100) Fill liquid refrigerant, recover the compressor oil and refrigerant mixture from the air conditioning system (100) through the other port of the refrigerant recovery filling machine (200), and separate the refrigerant and compress in the oil-air separator (201) Engine oil.
The compressor oil recovery method of the air conditioning system according to claim 14, wherein the two ports of the refrigerant recovery filling machine (200) are respectively connected to the high pressure side (107) and the high pressure side (107) of the air conditioning system (100). The low-pressure side (108) is connected. One port of the refrigerant recovery filling machine (200) is filled with liquid refrigerant to the air conditioning system (100), and the other port of the refrigerant recovery filling machine (200) is recovered and compressed from the air conditioning system (100). After the oil and refrigerant are mixed, and the refrigerant and compressor oil are separated in the oil-air separator (201), both cycle 1 and cycle 2 further include the following steps:

Close the control valve one (210), control valve two (211), control valve three (212) and control valve four between the two ports of the refrigerant recovery filling machine (200) and the air conditioning system (100) (213) Turn on the first compressor (202) until the pressure upstream of the first compressor (202) reaches a first preset value;

Turn off the first compressor (202), turn off the control valve seven (2016) between the inlet (20111) of the oil and gas separator (2011) and the air conditioning system (100), and turn on the oil and gas separator ( Control valve five (2014) at the oil outlet (20114) of 2011) opens the gap between the gaseous refrigerant outlet of the refrigerant storage tank (203) and the gaseous refrigerant inlet (20112) of the oil-gas separator (2011) Control valve 9 (214) to inject the gaseous refrigerant in the refrigerant storage tank (203) into the oil and gas separator (2011) to pressurize and discharge the compressor oil in the lower part of the oil and gas separator (2011) .
The compressor oil recovery method of an air conditioning system according to claim 14, wherein the refrigerant recovery and filling machine (200) further comprises a buffer container (2012), and the buffer container (2012) passes through a control valve five (2014) Communicate with the oil outlet (20114) of the oil and gas separator (2011);

The two ports of the refrigerant recovery and filling machine (200) are respectively connected to the high-pressure side (107) and the low-pressure side (108) of the air conditioning system (100), and one port from the refrigerant recovery and filling machine (200) Fill the air-conditioning system (100) with liquid refrigerant, and recover the compressor oil and refrigerant mixture from the air-conditioning system (100) through another port of the refrigerant recovery filling machine (200), and separate it in the oil-air separator (201) After refrigerant and compressor oil, cycle 1 and cycle 2 also include the following steps:

Close the control valve one (210), control valve two (211), control valve three (212) and control valve four between the two ports of the refrigerant recovery filling machine (200) and the air conditioning system (100) (213) Turn on the first compressor (202) until the pressure upstream of the first compressor (202) reaches a first preset value;

Open the control valve five (2014) between the oil outlet (20114) of the oil and gas separator (2011) and the buffer container (2012), and keep the first compressor (202) on until the first The pressure upstream of the compressor (202) reaches a second preset value;

Turn off the first compressor (202), turn off the control valve seven (2016) between the inlet (20111) of the oil and gas separator (2011) and the air conditioning system (100), and turn on the oil and gas separator ( Control valve five (2014) at the oil outlet (20114) of 2011) opens the gap between the gaseous refrigerant outlet of the refrigerant storage tank (203) and the gaseous refrigerant inlet (20112) of the oil-gas separator (2011) Control valve 9 (214) to inject the gaseous refrigerant in the refrigerant storage tank (203) into the oil and gas separator (2011) to pressurize and discharge the compressor oil in the lower part of the oil and gas separator (2011) .
The method for recovering compressor oil of an air conditioning system according to claim 16, after the method for recovering compressor oil of the air conditioning system executes at least one of the cycle 1 and the cycle 2, the method further comprises the following steps:

Close the control valve three (212) and control valve four (213) between the liquid refrigerant outlet end of the refrigerant recovery filling machine (200) and the air conditioning system (100), and turn on the oil-air separator (2011) The control valve seven (2016) between the inlet (20111) of the air conditioning system (100) and the air conditioning system (100) turns on the first compressor (202) until the pressure upstream of the first compressor (202) reaches the third preset Set value

Turn off the first compressor (202), turn off the control valve seven (2016) between the inlet (20111) of the oil and gas separator (2011) and the air conditioning system (100), and turn on the oil and gas separator ( Control valve five (2014) at the oil outlet (20114) of 2011), open the control valve six (2015) between the oil outlet (20114) of the buffer container (2012) and the old oil container (2013), Open the control valve 9 (214) between the gaseous refrigerant outlet of the refrigerant storage tank (203) and the gaseous refrigerant inlet (20112) of the oil and gas separator (2011), and inject the gaseous refrigerant in the refrigerant storage tank (203) To the oil and gas separator (2011) to discharge the compressor oil in the lower part of the oil and gas separator (2011) and the compressor oil in the buffer container (2012) into the used oil container (2013).