An oil filter self-cleaning system and a control method thereof, and an air conditioner

Abstract

An oil filter self-cleaning system, a control method thereof and an air conditioner, comprising: detecting in real time exhaust pressure, oil pressure, oil filter component back pressure, exhaust temperature, oil supply temperature, temperature before a first electromagnetic valve and temperature after the first electromagnetic valve of the oil filter self-cleaning system; calculating a difference between the exhaust pressure and the oil pressure as an oil pressure difference, if the oil pressure difference is in a set oil pressure difference abnormal range, controlling the compressor in the oil filter self-cleaning system to keep a current operation state, maintain the current operation state until entering an oil filter cleaning state after shutdown, immediately shut down and enter the oil filter cleaning state or control the first electromagnetic valve to close and then reopen based on the exhaust pressure, the oil pressure, the oil filter component back pressure, the exhaust temperature, the oil supply temperature, the temperature before the first electromagnetic valve and the temperature after the first electromagnetic valve. The present application realizes online cleaning of the oil filter component and pipeline, reduces manual disassembly and cleaning frequency, and improves operation reliability.

Description

Technical Field

[0001] This invention belongs to the field of air conditioning oil filtration technology, and more specifically, relates to an oil filter self-cleaning system and its control method, and an air conditioner. Background Technology

[0002] In an air conditioning system, the high-temperature, high-pressure gaseous refrigerant discharged from the compressor is separated from the lubricating oil by an oil separator. The lubricating oil then needs to be returned to the compressor's oil return port through the oil return line to ensure the compressor's lubrication and sealing performance.

[0003] Oil filter components are usually installed in the oil return line. They are located in the flow path between the oil separator and the compressor oil return port. Their main function is to intercept welding slag, oxide scale, metal shavings or large particulate impurities that may remain in the system. This prevents these impurities from clogging the very small inner diameter oil return capillary tube or entering the compressor cylinder with the lubricating oil, causing serious malfunctions such as scratches, wear or even cylinder jamming on the high-speed rotating scroll plate, piston or cylinder wall.

[0004] However, the oil filter components widely used in existing air conditioning units have a relatively simple structure, generally containing only one or more layers of metal filter screens, relying on the pore size of the filter screen for physical interception. In actual long-term operation, this solution has many inherent defects: On the one hand, as the air conditioning unit operates for a long time, the impurities trapped on the filter screen surface gradually increase, leading to increased resistance to oil return flow and insufficient oil return volume, which in turn causes the compressor exhaust temperature to rise and the oil level to drop. In severe cases, it can trigger the system's low-pressure protection or overheat protection, significantly affecting the reliability of the unit. On the other hand, when it is necessary to maintain or clean the filter screen, the entire filter must be completely removed from the oil return flow path, and special tools must be used to disassemble, clean, or replace the filter element. The operation process is cumbersome and often requires shutting down the unit to vent the refrigerant, increasing maintenance costs and time. This is especially true for large water chiller units or modular multi-split systems, where the maintenance difficulty is even more pronounced. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an oil filter self-cleaning system and its control method, as well as an air conditioner.

[0006] The present invention adopts the following technical solution.

[0007] The first aspect of the present invention provides an oil filter self-cleaning system, comprising: a compressor 1, an oil filter 2, a condenser 3, an electronic expansion valve 4, an evaporator 5, a first oil tank 6, a second oil tank 17, an electronic dosing level gauge 19, a first electric butterfly valve 7, a second electric butterfly valve 16, a third electric butterfly valve 18, a fourth electric butterfly valve 15, a fifth electric butterfly valve 20, an oil filter component 8, a check valve 9, a first oil pump 10, a second oil pump 14, a first filter 11, a second filter 21, a first solenoid valve 12, and a second solenoid valve 13, specifically: The compressor 1 is connected to the oil filter 2, and the oil filter 2 is connected to the compressor 1 in sequence through the condenser 3, the electronic expansion valve 4 and the evaporator 5; Furthermore, the oil filter 2 is connected to the compressor 1 in sequence via the first electric butterfly valve 7, the oil filter component 8, the first solenoid valve 12, and the fifth electric butterfly valve 20; The connection point between the oil filter component 8 and the first electric butterfly valve 7 is sequentially connected to the second electric butterfly valve 16, the second oil tank 17, the third electric butterfly valve 18, the first filter 11, the first oil tank 6, the second filter 21, the fourth electric butterfly valve 15, and the oil inlet of the first oil pump 10. The oil outlet of the first oil pump 10 is connected to the inlet of the one-way valve 9, and the outlet of the one-way valve 9 is connected to the connection point between the oil filter component 8 and the first solenoid valve 12. Furthermore, the oil filter component 8 is also connected to the oil inlet of the second oil pump 14 via the second solenoid valve 13, and the oil outlet of the second oil pump 14 is connected to the first oil tank 6. The electronic dosimeter 19 is used to measure the oil level in the first oil tank 6.

[0008] Preferably, the first electric butterfly valve 7 and the fifth electric butterfly valve 20 start and stop simultaneously.

[0009] Embodiment 2 of the present invention proposes a control method based on the oil filter self-cleaning system described in Embodiment 1 of the present invention, specifically as follows: Real-time monitoring of exhaust pressure, oil pressure, pressure after oil passage components, exhaust temperature, oil supply temperature, inlet temperature of the first solenoid valve 12, and outlet temperature of the first solenoid valve 12; calculation of the difference between exhaust pressure and oil pressure as oil pressure difference; If the oil pressure difference is within the set abnormal range, the system will make a preliminary judgment on whether there is a blockage based on the pressure after the oil filter component and the exhaust pressure. If there is a preliminary judgment on whether there is a blockage, the system will make a judgment on whether the blockage affects the operation of the unit based on the difference between the pressure after the oil filter component and the exhaust pressure. If not, the compressor 1 will maintain the current operating state until it is shut down and enters the oil filter cleaning state. If so, the compressor 1 will immediately shut down and enter the oil filter cleaning state. If it is initially determined that there is no blockage, then based on the exhaust temperature, oil supply temperature, and the inlet and outlet temperatures of the first solenoid valve 12, it is determined whether there is an abnormality and the type of abnormality. The types of abnormalities include blockage and the first solenoid valve 12 not being fully open. If it is determined that there is no abnormality, the compressor 1 maintains its current operating state. If it is determined that the first solenoid valve 12 is not fully open, the first solenoid valve 12 is closed and then reopened, and an abnormality detection of the first solenoid valve 12 is performed. If it is determined that there is a blockage, the compressor 1 is immediately shut down and enters the oil filter cleaning state.

[0010] Preferably, the exhaust pressure is the pressure at one end of the compressor 1, and one end of the compressor 1 is directly connected to the oil filter 2; the oil pressure and the pressure after the oil filter component are the pressures at one end and the other end of the oil filter component 8, respectively; one end of the oil filter component 8 is directly connected to the first electric butterfly valve 7; and the other end of the oil filter component 8 is directly connected to the first solenoid valve 12. The exhaust temperature and the oil supply temperature are the temperatures of one end and the other end of the oil filter 2, respectively. One end of the oil filter 2 is directly connected to the compressor 1. The other end of the oil filter 2 is directly connected to the first electric butterfly valve 7. The inlet temperature and outlet temperature of the first solenoid valve 12 are the temperatures of one end and the other end of the first solenoid valve 12, respectively. One end of the first solenoid valve 12 is directly connected to the outlet end of the check valve 9. The other end of the first solenoid valve 12 is directly connected to the fifth electric butterfly valve 20.

[0011] Preferably, the initial determination of whether there is a blockage is based on the pressure after the oil passage component and the exhaust pressure. If a blockage is initially determined, the determination of whether the blockage affects the unit operation is based on the difference between the pressure after the oil passage component and the exhaust pressure. Specifically: If the pressure difference between the oil filter component and the exhaust pressure is less than or equal to the set first pressure difference threshold, it is preliminarily determined that there is no blockage. If the pressure difference between the oil filter component and the exhaust pressure is greater than the set first pressure difference threshold and less than or equal to the set second pressure difference threshold, it is determined that the blockage does not affect the operation of the unit. If the pressure difference between the oil filter component and the exhaust pressure is greater than the set second pressure difference threshold, it is determined that the blockage is affecting the operation of the unit. The second pressure difference threshold is greater than the first pressure difference threshold.

[0012] Preferably, the determination of whether an abnormality exists and the type of abnormality is determined based on the exhaust temperature, oil supply temperature, and the inlet and outlet temperatures of the first solenoid valve 12, specifically as follows: Calculate the difference between the exhaust temperature and the oil supply temperature. If the difference between the exhaust temperature and the oil supply temperature is less than or equal to the set oil filter temperature difference threshold, it is judged to be normal, and compressor 1 maintains its current operating state. If the difference between the exhaust temperature and the oil supply temperature is greater than the set oil filter temperature difference threshold but less than or equal to the sum of the set oil filter temperature difference threshold and the set temperature margin, then the difference between the inlet temperature and the outlet temperature of the first solenoid valve 12 is calculated. If the difference between the inlet temperature and the outlet temperature of the first solenoid valve 12 is less than or equal to the set solenoid valve temperature difference threshold, it is determined that there is no abnormality and the compressor 1 maintains its current operating state. If the difference between the inlet temperature and the outlet temperature of the first solenoid valve 12 is greater than the set solenoid valve temperature difference threshold, it is determined that the first solenoid valve 12 is not fully open, the first solenoid valve 12 is reset and the first solenoid valve 12 abnormality detection is performed. If the difference between the exhaust temperature and the oil supply temperature is greater than the sum of the set oil filter temperature difference threshold and the set temperature margin, then the difference between the temperature before and after the first solenoid valve 12 is calculated. If the difference between the temperature before and after the first solenoid valve 12 is less than or equal to the set solenoid valve temperature difference threshold, it is judged to be blocked, and the compressor 1 is immediately shut down and enters the oil filter cleaning state. If the difference between the temperature before and after the first solenoid valve 12 is greater than the set solenoid valve temperature difference threshold, it is judged that the first solenoid valve 12 is not fully open. Then the first solenoid valve 12 is closed and reopened, and the abnormality detection of the first solenoid valve 12 is performed.

[0013] Preferably, the cleanliness state of the oil filter is as follows: Record the electronic dosimeter level 19 as the first scale, close the first electric butterfly valve 7, open the second solenoid valve 13, start the second oil pump 14, and recover the oil in the pipeline into the first oil tank 6. After the recovery is completed, close the second oil pump 14 and the second solenoid valve 13. Open the fourth electric butterfly valve 15, the second electric butterfly valve 16, the third electric butterfly valve 18 and the first oil pump 10. The oil flows into the oil flow device 8, into the second oil tank 17, and after being filtered by the first filter 11, it flows into the first oil tank 6. After the first set cycle, close the fourth electric butterfly valve 15, the second electric butterfly valve 16, the third electric butterfly valve 18 and the first oil pump 10. Open the first oil pump 10 and the fourth electric butterfly valve 15, and draw oil from the first oil tank 6 back into the pipeline until the electronic dosing level gauge 19 returns to the first scale. Then close the first oil pump 10 and the fourth electric butterfly valve 15.

[0014] Preferably, the recycling is completed as follows: When the oil in the pipeline is recycled into the first oil tank 6, the oil pressure and the pressure after the oil passer component are monitored in real time. When the oil pressure or the pressure after the oil passer component is less than the set minimum pressure threshold, the recycling is considered to be complete.

[0015] Preferably, resetting the first solenoid valve 12 and performing anomaly detection on the first solenoid valve 12 specifically involves: After closing, immediately reopen and continue running the set second cycle. Then, check again whether the temperature difference between the valve inlet and outlet of the first solenoid valve 12 is greater than the set solenoid valve temperature difference threshold. If so, the opening degree of the first solenoid valve 12 is considered abnormal.

[0016] A third aspect of the present invention provides an air conditioner that integrates the oil filter self-cleaning system described in the first aspect of the present invention.

[0017] The beneficial effects of this invention are compared with those of the prior art: 1. This invention, by setting up a first oil tank, a second oil tank, multiple electric butterfly valves, an oil pump, and a filter, and forming a switchable circulating filtration branch with the oil filter components and the return oil pipeline, enables the oil to be driven by the first oil pump to flow through the second oil tank and the first filter for re-filtration without removing the oil filter components. The cleaned oil is then sent back to the return oil pipeline via a one-way valve. At the same time, the second oil pump can recover residual oil in the pipeline to the first oil tank, thereby realizing online cleaning of the oil filter components and pipeline, effectively avoiding filtration failure caused by impurity accumulation, reducing the frequency of manual disassembly and cleaning, and improving the operational reliability of the compressor.

[0018] 2. By opening and closing the first and fifth electric butterfly valves simultaneously, this invention ensures that the main return oil passage is cut off or opened at the same time, avoiding oil flow fluctuations or pressure changes caused by inconsistent valve actions, and improving the stability of system switching.

[0019] 3. This invention monitors exhaust pressure, oil pressure, pressure after oil passage components, exhaust temperature, oil supply temperature, and temperatures before and after the solenoid valve in real time, and judges blockage or abnormal solenoid valve opening based on pressure and temperature differences. It can accurately distinguish the severity of blockage and fault type, thereby triggering cleaning or shutdown protection in time before affecting unit operation, avoiding misjudgment or excessive maintenance.

[0020] 4. By defining the specific installation positions of each pressure and temperature measuring point, this invention enables the measured values ​​to accurately reflect the pressure drop across the oil passage components and the temperature difference across the solenoid valve, providing an accurate and reliable data basis for fault diagnosis and improving the consistency of judgment.

[0021] 5. This invention quantifies the degree of blockage into three states: no impact on operation, impact on operation, and no blockage. This allows the control system to take differentiated responses, such as maintaining, delaying cleaning, or immediately shutting down, based on different severity levels, thereby optimizing the unit's operation and maintenance strategies.

[0022] 6. This invention uses the difference between exhaust temperature and oil supply temperature, combined with the temperature difference before and after the solenoid valve, to make a joint judgment. This can effectively distinguish between two fault modes: oil filter blockage and solenoid valve not being fully open. This avoids misjudgment caused by a single temperature indicator and improves the accuracy of fault location.

[0023] 7. This invention achieves fully automated cleaning by first recovering pipeline oil in a clean state, then circulating and flushing the oil filter components and pipelines, and finally replenishing the oil to the original level. During the cleaning process, the first oil tank is used as an oil buffer and metering reference to ensure the oil balance of the system. Cleaning can be completed without disassembling the filter.

[0024] 8. In the process of recovering oil, the present invention uses the oil pressure or the pressure after the oil passer component being lower than the minimum pressure threshold as the judgment condition for the completion of recovery. This ensures that the oil in the pipeline is fully drained, and avoids the residual oil from diluting or interfering with the rinsing effect in subsequent cleaning cycles.

[0025] 9. By resetting the first solenoid valve (reopening it after closing) and running it for a second cycle, the present invention can verify whether the opening of the first solenoid valve has returned to normal, thereby confirming whether the fault was caused by temporary jamming and reducing unnecessary downtime for cleaning operations.

[0026] 10. This invention integrates an oil filter self-cleaning system into the air conditioner, enabling the air conditioning unit to have online self-cleaning and fault self-diagnosis capabilities, significantly reducing the risk of oil return blockage, extending compressor life, reducing manual maintenance costs, and improving the overall reliability of the unit. Attached Figure Description

[0027] Figure 1 This is a structural diagram of the oil filter self-cleaning system of the present invention; Figure 2 This is a flowchart illustrating the control of the oil filter self-cleaning system based on various pressures according to the present invention. Figure 3 This is a flowchart illustrating the control of the oil filter self-cleaning system based on various temperatures according to the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this invention. The embodiments described in this application are merely some embodiments of this invention, and not all embodiments. Based on the spirit of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this invention.

[0029] like Figure 1As shown, Embodiment 1 of the present invention proposes an oil filter self-cleaning system, comprising: a compressor 1, an oil filter 2, a condenser 3, an electronic expansion valve 4, an evaporator 5, a first oil tank 6, a second oil tank 17, an electronic dosing level gauge 19, a first electric butterfly valve 7, a second electric butterfly valve 16, a third electric butterfly valve 18, a fourth electric butterfly valve 15, a fifth electric butterfly valve 20, an oil filter component 8, a check valve 9, a first oil pump 10, a second oil pump 14, a first filter 11, a second filter 21, a first solenoid valve 12, and a second solenoid valve 13, specifically: The compressor 1 is connected to the oil filter 2, and the oil filter 2 is connected to the compressor 1 in sequence through the condenser 3, the electronic expansion valve 4 and the evaporator 5; Furthermore, the oil filter 2 is connected to the compressor 1 in sequence via the first electric butterfly valve 7, the oil filter component 8, the first solenoid valve 12, and the fifth electric butterfly valve 20; The connection point between the oil filter component 8 and the first electric butterfly valve 7 is sequentially connected to the second electric butterfly valve 16, the second oil tank 17, the third electric butterfly valve 18, the first filter 11, the first oil tank 6, the second filter 21, the fourth electric butterfly valve 15, and the oil inlet of the first oil pump 10. The oil outlet of the first oil pump 10 is connected to the inlet of the one-way valve 9, and the outlet of the one-way valve 9 is connected to the connection point between the oil filter component 8 and the first solenoid valve 12. Furthermore, the oil filter component 8 is also connected to the oil inlet of the second oil pump 14 via the second solenoid valve 13, and the oil outlet of the second oil pump 14 is connected to the first oil tank 6. The electronic dosimeter 19 is used to measure the oil level in the first oil tank 6.

[0030] It should be noted that this embodiment, by setting up a first oil tank, a second oil tank, multiple electric butterfly valves, an oil pump, and a filter, and forming a switchable circulating filtration branch with the oil filter components and the return oil pipeline, can use the first oil pump to drive the oil to flow through the second oil tank and the first filter for re-filtration without removing the oil filter components. The cleaned oil is then sent back to the return oil pipeline through a one-way valve. At the same time, the second oil pump can recover the residual oil in the pipeline to the first oil tank, thereby realizing online cleaning of the oil filter components and pipeline, effectively avoiding filtration failure caused by the accumulation of impurities, reducing the frequency of manual disassembly and cleaning, and improving the operational reliability of the compressor.

[0031] In this preferred embodiment, the first electric butterfly valve 7 and the fifth electric butterfly valve 20 start and stop simultaneously.

[0032] It should be noted that in this embodiment, by opening and stopping the first electric butterfly valve and the fifth electric butterfly valve simultaneously, the main return oil passage can be cut off or opened at the same time, avoiding oil flow fluctuations or pressure changes caused by inconsistent valve actions, and improving the stability of system switching.

[0033] Embodiment 2 of the invention proposes a control method based on the oil filter self-cleaning system described in Embodiment 1 of the invention, specifically as follows: Real-time monitoring of exhaust pressure, oil pressure, pressure after the oil passage component, exhaust temperature, oil supply temperature, inlet temperature of the first solenoid valve 12, and outlet temperature of the first solenoid valve 12; calculation of the difference between exhaust pressure and oil pressure as the oil pressure differential, using the following formula:

[0034] in, This refers to the exhaust pressure; This refers to the hydraulic pressure.

[0035] If the oil pressure difference is within the set abnormal range, that is, when Then proceed to the next step; among which This represents the lower limit of the abnormal range for oil pressure differences. This represents the upper limit of the abnormal range for oil pressure differences. The next steps are as follows: Figure 2 As shown, based on the pressure after the oil filter component and the exhaust pressure, it is initially determined whether there is a blockage. If it is initially determined to be blocked, it is determined whether the blockage affects the operation of the unit based on the difference between the pressure after the oil filter component and the exhaust pressure. If not, the compressor 1 maintains the current operating state until it is shut down and enters the oil filter cleaning state. If so, the compressor 1 is immediately shut down and enters the oil filter cleaning state. like Figure 3 As shown, if it is initially determined that there is no blockage, then based on the exhaust temperature, oil supply temperature, and the inlet and outlet temperatures of the first solenoid valve 12, it is determined whether there is an abnormality and the type of abnormality. The types of abnormalities include blockage and the first solenoid valve 12 not being fully open. If it is determined that there is no abnormality, the compressor 1 maintains its current operating state. If it is determined that the first solenoid valve 12 is not fully open, the first solenoid valve 12 is closed and then reopened, and an abnormality detection of the first solenoid valve 12 is performed. If it is determined that there is a blockage, the compressor 1 is immediately shut down and enters the oil filter cleaning state.

[0036] It should be noted that, due to changes in system status, malfunctions of pressure sensors, or malfunctions of temperature sensors causing misjudgments, both pressure and temperature are included in the judgment conditions, with pressure having higher priority. Therefore, the judgment is based on pressure first, followed by temperature judgment, to avoid misjudging blockages as normal operating conditions due to errors caused by pressure sensor malfunctions, etc. Regarding temperature, there are two influencing components in the return oil flow path: one is the oil filter, and the other is the first solenoid valve. The first solenoid valve is a pipeline component with only switching function, and there may be a situation where the coil drive is obstructed and it does not open completely. When it is not fully opened, throttling will occur, resulting in a temperature difference before and after. If the temperature difference is small, the influence can be eliminated; if the temperature difference is large, the electronic expansion valve will be reset and reopened.

[0037] This embodiment monitors exhaust pressure, oil pressure, pressure after the oil passage component, exhaust temperature, oil supply temperature, and the temperature before and after the solenoid valve in real time. Based on the pressure difference and temperature difference, it can stratify blockage or abnormal solenoid valve opening, accurately distinguish the severity of blockage and fault type, and thus trigger cleaning or shutdown protection in time before affecting the operation of the unit, avoiding misjudgment or excessive maintenance.

[0038] In this preferred embodiment, the exhaust pressure is the pressure at one end of the compressor 1, and one end of the compressor 1 is directly connected to the oil filter 2; the oil pressure and the pressure after the oil filter component are the pressures at one end and the other end of the oil filter component 8, respectively; one end of the oil filter component 8 is directly connected to the first electric butterfly valve 7; and the other end of the oil filter component 8 is directly connected to the first solenoid valve 12. The exhaust temperature and the oil supply temperature are the temperatures of one end and the other end of the oil filter 2, respectively. One end of the oil filter 2 is directly connected to the compressor 1. The other end of the oil filter 2 is directly connected to the first electric butterfly valve 7. The inlet temperature and outlet temperature of the first solenoid valve 12 are the temperatures of one end and the other end of the first solenoid valve 12, respectively. One end of the first solenoid valve 12 is directly connected to the outlet end of the check valve 9. The other end of the first solenoid valve 12 is directly connected to the fifth electric butterfly valve 20.

[0039] It should be noted that this embodiment limits the specific installation locations of each pressure and temperature measuring point, so that the measured values ​​can truly reflect the pressure drop across the oil passage component and the temperature difference across the solenoid valve, providing an accurate and reliable data basis for fault diagnosis and improving the consistency of judgment.

[0040] In this preferred embodiment, the initial judgment of whether there is a blockage is based on the pressure after the oil passage component and the exhaust pressure. If a blockage is initially determined, the difference between the pressure after the oil passage component and the exhaust pressure is used to determine whether the blockage affects the unit operation. Specifically: If the pressure difference between the oil filter component and the exhaust pressure is less than or equal to the set first pressure difference threshold, it is preliminarily determined that there is no blockage (i.e., it is preliminarily determined that the subsequent compressor 1 will maintain its current operating state). If the pressure difference between the oil filter component and the exhaust pressure is greater than the set first pressure difference threshold and less than or equal to the set second pressure difference threshold, it is determined that the blockage does not affect the operation of the unit. If the pressure difference between the oil filter component and the exhaust pressure is greater than the set second pressure difference threshold, it is determined that the blockage is affecting the operation of the unit. The second pressure difference threshold is greater than the first pressure difference threshold; In summary, the preliminary assessment of the blockage, and whether the blockage affects the unit's operation, is as follows: when If the condition is as follows, it is initially determined that there is no blockage, that is, the compressor 1 maintains its current operating state and is subsequently re-evaluated based on temperature (specifically including exhaust temperature, oil supply temperature, and the temperature before and after the first solenoid valve 12). when If the blockage is not significant and does not affect the unit's operation, the oil filter will be cleaned after compressor 1 is shut down. when If the situation is initially determined to be a blockage that is affecting the unit's operation, compressor 1 should be immediately shut down and put into oil filter cleaning mode. in, The pressure after the oil passage component; This refers to the exhaust pressure; , The first and second pressure difference thresholds are set based on experience.

[0041] It should be noted that this embodiment quantifies the degree of blockage into three states: no impact on operation, impact on operation, and no blockage. This allows the control system to take differentiated responses, such as maintaining, delaying cleaning, or immediately shutting down, based on different severity levels, thereby optimizing the unit's operation and maintenance strategies.

[0042] In this preferred embodiment, the determination of whether an abnormality exists and the type of abnormality is determined based on the exhaust temperature, oil supply temperature, and the inlet and outlet temperatures of the first solenoid valve 12, specifically includes: Calculate the difference between the exhaust temperature and the oil supply temperature. If the difference between the exhaust temperature and the oil supply temperature is less than or equal to the set oil filter temperature difference threshold, it is judged to be normal, and compressor 1 maintains its current operating state. If the difference between the exhaust temperature and the oil supply temperature is greater than the set oil filter temperature difference threshold but less than or equal to the sum of the set oil filter temperature difference threshold and the set temperature margin, then the difference between the inlet temperature and the outlet temperature of the first solenoid valve 12 is calculated. If the difference between the inlet temperature and the outlet temperature of the first solenoid valve 12 is less than or equal to the set solenoid valve temperature difference threshold, it is determined that there is no abnormality and the compressor 1 maintains its current operating state. If the difference between the inlet temperature and the outlet temperature of the first solenoid valve 12 is greater than the set solenoid valve temperature difference threshold, it is determined that the first solenoid valve 12 is not fully open, the first solenoid valve 12 is reset and the first solenoid valve 12 abnormality detection is performed. If the difference between the exhaust temperature and the oil supply temperature is greater than the sum of the set oil filter temperature difference threshold and the set temperature margin, then the difference between the temperature before and after the first solenoid valve 12 is calculated. If the difference between the temperature before and after the first solenoid valve 12 is less than or equal to the set solenoid valve temperature difference threshold, it is judged to be blocked, and the compressor 1 is immediately shut down and enters the oil filter cleaning state. If the difference between the temperature before and after the first solenoid valve 12 is greater than the set solenoid valve temperature difference threshold, it is judged that the first solenoid valve 12 is not fully open. Then the first solenoid valve 12 is closed and reopened, and the abnormality detection of the first solenoid valve 12 is performed.

[0043] In summary, the determination of whether something is abnormal and the type of abnormality are as follows: when If the condition is not abnormal, compressor 1 will maintain its current operating state. when When, then calculate ,like If it is normal, compressor 1 will maintain its current operating state. If so, it is determined that the first solenoid valve 12 is not fully open; when When, then calculate ,like If this is detected as a blockage, compressor 1 will immediately shut down and enter the oil filter cleaning state. If so, it is determined that the first solenoid valve 12 is not fully open; in, , , and These are the exhaust temperature, oil supply temperature, and the inlet and outlet temperatures of the first solenoid valve 12, respectively. The set oil filter temperature difference threshold, For the set temperature margin, The temperature difference thresholds for the solenoid valves are all set based on experience.

[0044] It should be noted that this embodiment uses the difference between exhaust temperature and oil supply temperature, combined with the temperature difference before and after the solenoid valve, to make a joint judgment. This can effectively distinguish between two fault modes: oil filter blockage and solenoid valve not being fully open. This avoids misjudgment caused by a single temperature indicator and improves the accuracy of fault location.

[0045] In this preferred embodiment, the cleanliness state of the oil filter is specifically as follows: It should be noted that the oil filter cleaning operation should be performed after the compressor is turned off; Record the electronic dosimeter level 19 as the first scale, close the first electric butterfly valve 7, open the second solenoid valve 13, start the second oil pump 14, and recover the oil in the pipeline into the first oil tank 6. After the recovery is completed, close the second oil pump 14 and the second solenoid valve 13. It should be noted that the above steps involve recovering the oil in the oil filter components before cleaning (i.e., draining the oil), and determining whether the recovery is complete by measuring the pressure (specifically, the oil pressure and the pressure after the oil passes through the filter components).

[0046] Open the fourth electric butterfly valve 15, the second electric butterfly valve 16, the third electric butterfly valve 18 and the first oil pump 10. The oil flows into the oil flow device 8, into the second oil tank 17, and after being filtered by the first filter 11, it flows into the first oil tank 6. After a set first cycle m, close the fourth electric butterfly valve 15, the second electric butterfly valve 16, the third electric butterfly valve 18 and the first oil pump 10. It should be noted that the above steps are backwashing of the oil filter components to flush away and remove impurities adsorbed on the filter element.

[0047] Open the first oil pump 10 and the fourth electric butterfly valve 15, and draw the oil from the first oil tank 6 back into the pipeline until the electronic dosing level gauge 19 returns to the first scale. Then close the first oil pump 10 and the fourth electric butterfly valve 15. It should be noted that the above steps involve refilling the drained oil after cleaning.

[0048] It should be noted that this embodiment achieves fully automated cleaning by first recovering the pipeline oil, then circulating and flushing the oil filter components and pipelines, and finally replenishing the oil to the original level. During the cleaning process, the first oil tank is used as an oil buffer and metering reference to ensure the oil balance of the system. Cleaning can be completed without disassembling the filter.

[0049] In this preferred embodiment, the completion of the recycling specifically includes: When the oil in the pipeline is recycled back into the first oil tank 6, the oil pressure and the pressure after the oil passer component are monitored in real time. When the oil pressure or the pressure after the oil passer component is lower than the set minimum pressure threshold, the recycling is considered complete. when or hour, in, The minimum pressure threshold is set based on experience and is expressed in kPa.

[0050] It should be noted that in this embodiment, the oil pressure or the pressure after the oil passer component is lower than the minimum pressure threshold is used as the condition for determining the completion of the recovery. This ensures that the oil in the pipeline is fully drained, and avoids the residual oil from diluting or interfering with the rinsing effect in subsequent cleaning cycles.

[0051] In this preferred embodiment, resetting the first solenoid valve 12 and performing anomaly detection on the first solenoid valve 12 specifically involves: After closing, immediately reopen and continue running the set second cycle n. Then, determine again whether the difference between the temperature before and after the first solenoid valve 12 is greater than the set solenoid valve temperature difference threshold. If so, the opening degree of the first solenoid valve 12 is considered abnormal.

[0052] It should be noted that in this embodiment, by resetting the first solenoid valve (reopening it after closing) and running it for a second cycle, the temperature difference before and after the valve is detected again, it can be verified whether the opening of the first solenoid valve has returned to normal, thereby confirming whether the fault was caused by temporary jamming and reducing unnecessary downtime for cleaning operations.

[0053] Embodiment 3 of the present invention proposes an air conditioner that integrates the oil filter self-cleaning system described in Embodiment 1 of the present invention.

[0054] It should be noted that this embodiment integrates the oil filter self-cleaning system into the air conditioner, enabling the air conditioning unit to have online self-cleaning and fault self-diagnosis capabilities, significantly reducing the risk of oil return blockage, extending compressor life, reducing manual maintenance costs, and improving the overall reliability of the unit.

[0055] This disclosure can be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of this disclosure.

[0056] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination of the foregoing. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0057] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0058] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. An oil filter self-cleaning system, comprising: The compressor (1), oil filter (2), condenser (3), electronic expansion valve (4), evaporator (5), first oil tank (6), second oil tank (17), electronic dosing level gauge (19), first electric butterfly valve (7), second electric butterfly valve (16), third electric butterfly valve (18), fourth electric butterfly valve (15), fifth electric butterfly valve (20), oil filter component (8), check valve (9), first oil pump (10), second oil pump (14), first filter (11), second filter (21), first solenoid valve (12) and second solenoid valve (13) are characterized in that: The compressor (1) is connected to the oil filter (2), and the oil filter (2) is connected to the compressor (1) in sequence through the condenser (3), the electronic expansion valve (4) and the evaporator (5). The oil filter (2) is connected to the compressor (1) in sequence through the first electric butterfly valve (7), the oil filter component (8), the first solenoid valve (12) and the fifth electric butterfly valve (20); The connection point between the oil filter component (8) and the first electric butterfly valve (7) is sequentially connected through the second electric butterfly valve (16), the second oil tank (17), the third electric butterfly valve (18), the first filter (11), the first oil tank (6), the second filter (21), the fourth electric butterfly valve (15), and the oil inlet of the first oil pump (10). The oil outlet of the first oil pump (10) is connected to the inlet of the one-way valve (9), and the outlet of the one-way valve (9) is connected to the connection point between the oil filter component (8) and the first solenoid valve (12). Furthermore, the oil filter component (8) is also connected to the oil inlet of the second oil pump (14) via the second solenoid valve (13), and the oil outlet of the second oil pump (14) is connected to the first oil tank (6); The electronic dosimeter (19) is used to measure the oil level in the first oil tank (6).

2. The oil filter self-cleaning system according to claim 1, characterized in that: The first electric butterfly valve (7) and the fifth electric butterfly valve (20) start and stop simultaneously.

3. A control method for the oil filter self-cleaning system according to any one of claims 1-2, characterized in that: Real-time detection of exhaust pressure, oil pressure, pressure after oil passage component, exhaust temperature, oil supply temperature, valve inlet temperature of the first solenoid valve (12) and valve outlet temperature of the first solenoid valve (12); calculate the difference between exhaust pressure and oil pressure as oil pressure difference; If the oil pressure difference is within the set abnormal range of oil pressure difference, the oil filter component is initially judged to be blocked based on the pressure after the oil filter component and the exhaust pressure. If it is initially judged to be blocked, the difference between the pressure after the oil filter component and the exhaust pressure is used to judge whether the blockage affects the operation of the unit. If not, the compressor (1) maintains the current operating state until it is shut down and enters the oil filter cleaning state. If so, the compressor (1) is immediately shut down and enters the oil filter cleaning state. If it is initially determined that there is no blockage, then based on the exhaust temperature, oil supply temperature, and the temperature before and after the first solenoid valve (12), it is determined whether there is an abnormality and the type of abnormality. The types of abnormalities include blockage and the first solenoid valve (12) not being fully open. If it is determined that there is no abnormality, the compressor (1) maintains its current operating state. If it is determined that the first solenoid valve (12) is not fully open, the first solenoid valve (12) is closed and then reopened, and the abnormality detection of the first solenoid valve (12) is performed. If it is determined that there is a blockage, the compressor (1) is immediately shut down and enters the oil filter cleaning state.

4. The control method for the oil filter self-cleaning system according to claim 3, characterized in that: The exhaust pressure is the pressure at one end of the compressor (1), and one end of the compressor (1) is directly connected to the oil filter (2); the oil pressure and the pressure after the oil filter component are the pressures at one end and the other end of the oil filter component (8), respectively, and one end of the oil filter component (8) is directly connected to the first electric butterfly valve (7); the other end of the oil filter component (8) is directly connected to the first solenoid valve (12); The exhaust temperature and the oil supply temperature are the temperatures of one end and the other end of the oil filter (2), respectively. One end of the oil filter (2) is directly connected to the compressor (1); the other end of the oil filter (2) is directly connected to the first electric butterfly valve (7); the inlet temperature and outlet temperature of the first solenoid valve (12) are the temperatures of one end and the other end of the first solenoid valve (12), respectively. One end of the first solenoid valve (12) is directly connected to the outlet end of the check valve (9); the other end of the first solenoid valve (12) is directly connected to the fifth electric butterfly valve (20).

5. The control method for the oil filter self-cleaning system according to claim 3, characterized in that: The method involves initially determining whether a blockage exists based on the pressure after the oil passage component and the exhaust pressure. If a blockage is initially determined, the method then determines whether the blockage affects unit operation based on the difference between the pressure after the oil passage component and the exhaust pressure. Specifically: If the pressure difference between the oil filter component and the exhaust pressure is less than or equal to the set first pressure difference threshold, it is preliminarily determined that there is no blockage. If the pressure difference between the oil filter component and the exhaust pressure is greater than the set first pressure difference threshold and less than or equal to the set second pressure difference threshold, it is determined that the blockage does not affect the operation of the unit. If the pressure difference between the oil filter component and the exhaust pressure is greater than the set second pressure difference threshold, it is determined that the blockage is affecting the operation of the unit. The second pressure difference threshold is greater than the first pressure difference threshold.

6. The control method for the oil filter self-cleaning system according to claim 3, characterized in that: The method for determining whether an abnormality exists and the type of abnormality is based on exhaust temperature, oil supply temperature, and the inlet and outlet temperatures of the first solenoid valve (12). Specifically: Calculate the difference between the exhaust temperature and the oil supply temperature. If the difference between the exhaust temperature and the oil supply temperature is less than or equal to the set oil filter temperature difference threshold, it is judged to be normal and the compressor (1) maintains the current operating state. If the difference between the exhaust temperature and the oil supply temperature is greater than the set oil filter temperature difference threshold and less than or equal to the sum of the set oil filter temperature difference threshold and the set temperature margin, then the difference between the temperature before and after the first solenoid valve (12) is calculated. If the difference between the temperature before and after the first solenoid valve (12) is less than or equal to the set solenoid valve temperature difference threshold, it is judged to be normal and the compressor (1) maintains its current operating state. If the difference between the temperature before and after the first solenoid valve (12) is greater than the set solenoid valve temperature difference threshold, it is judged that the first solenoid valve (12) is not fully open, the first solenoid valve (12) is reset and the first solenoid valve (12) is detected as abnormal. If the difference between the exhaust temperature and the oil supply temperature is greater than the sum of the set oil filter temperature difference threshold and the set temperature margin, then the difference between the temperature before and after the first solenoid valve (12) is calculated. If the difference between the temperature before and after the first solenoid valve (12) is less than or equal to the set solenoid valve temperature difference threshold, it is judged to be blocked, and the compressor (1) is immediately shut down and enters the oil filter cleaning state. If the difference between the temperature before and after the first solenoid valve (12) is greater than the set solenoid valve temperature difference threshold, it is judged that the first solenoid valve (12) is not fully open. Then the first solenoid valve (12) is closed and reopened, and the abnormality detection of the first solenoid valve (12) is performed.

7. The control method for the oil filter self-cleaning system according to claim 3, characterized in that: The specific cleanliness status of the oil filter is as follows: Record the scale of the electronic dosing level gauge (19) as the first scale, close the first electric butterfly valve (7), open the second solenoid valve (13), start the second oil pump (14), and recover the oil in the pipeline into the first oil tank (6). After the recovery is completed, close the second oil pump (14) and the second solenoid valve (13). Open the fourth electric butterfly valve (15), the second electric butterfly valve (16), the third electric butterfly valve (18) and the first oil pump (10). The oil flows through the oil flow device (8) and into the second oil tank (17). After being filtered by the first filter (11), it flows into the first oil tank (6). After the first set cycle, close the fourth electric butterfly valve (15), the second electric butterfly valve (16), the third electric butterfly valve (18) and the first oil pump (10). Open the first oil pump (10) and the fourth electric butterfly valve (15), draw the oil from the first oil tank (6) back into the pipeline until the scale of the electronic dosing level gauge (19) returns to the first scale, and close the first oil pump (10) and the fourth electric butterfly valve (15).

8. The control method for the oil filter self-cleaning system according to claim 7, characterized in that: The recycling process is complete, specifically as follows: When the oil in the pipeline is recycled into the first oil tank (6), the oil pressure and the pressure after the oil passer component are detected in real time. When the oil pressure or the pressure after the oil passer component is less than the set minimum pressure threshold, the recycling is considered to be complete.

9. The control method for the oil filter self-cleaning system according to claim 6, characterized in that: The process of resetting the first solenoid valve (12) and performing anomaly detection on the first solenoid valve (12) specifically involves: After closing, immediately reopen and continue running the set second cycle. Then, determine again whether the difference between the temperature before and after the first solenoid valve (12) is greater than the set solenoid valve temperature difference threshold. If so, the opening degree of the first solenoid valve (12) is considered abnormal.

10. An air conditioner, characterized in that, The oil filter self-cleaning system according to any one of claims 1-2 is integrated.

Images