Device and method for testing oil circulation rate of heat pump air conditioning system

Abstract

The invention discloses an oil circulation rate testing device and method of a heat pump air-conditioning system. The oil circulation rate testing device of the heat pump air-conditioning system comprises a tester and a control valve group. The test meter and the control valve group are arranged on a connecting pipeline of the first heat exchanger and the second heat exchanger; in a refrigeration working condition test mode, the control valve group can enable the first heat exchanger, the test meter, the expansion valve and the second heat exchanger to be communicated in sequence; in a heating working condition test mode, the control valve group can enable the second heat exchanger, the test meter, the expansion valve and the first heat exchanger to be communicated in sequence; in the off-line mode, the first heat exchanger, the expansion valve and the second heat exchanger can be sequentially communicated through the control valve set, and communication of the first heat exchanger, the test meter and the second heat exchanger can be cut off. The heat pump air-conditioning system can ensure that a refrigerant flows into the input end of the tester in a liquid form from the output end of the condenser when the heat pump air-conditioning system is in a refrigeration working condition and a heating working condition, so that the precision of the tester and the accuracy of the oil circulation rate of the system are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of air - conditioning systems, and particularly to an oil circulation rate testing device for a heat pump air - conditioning system. Background Art

[0002] The oil circulation rate is closely related to the performance of the air - conditioning system. At present, an oil circulation rate tester is generally used to measure the oil circulation rate of the air - conditioning system, and the oil circulation rate tester must be located at the outlet of the condenser during testing to ensure that the refrigerant entering the oil circulation rate tester is a liquid refrigerant. Therefore, the oil circulation rate of the air - conditioning system is generally tested and studied under refrigeration conditions.

[0003] Existing heat pump air - conditioning systems are configured with two operating conditions: refrigeration and heating. When the heat pump air - conditioning system switches from the refrigeration condition to the heating condition, the condenser under the refrigeration condition becomes the evaporator under the heating condition, and the evaporator under the refrigeration condition becomes the condenser under the heating condition, and the refrigerant in the oil circulation rate tester flows unidirectionally (i.e., the liquid refrigerant can only flow in from one end and out from the other end). Therefore, in order to ensure the accuracy of the test results under the heating condition, there are currently two methods for testing the oil circulation rate of heat pump air - conditioning systems:

[0004] First, change the measurement position of the oil circulation rate tester. The existing method of changing the oil circulation rate tester is to manually remove the oil circulation rate tester, convert its direction, and then reinstall it into the heat pump air - conditioning system. However, the above - mentioned method of changing the measurement position of the oil circulation rate tester not only increases the workload of pipeline disassembly and assembly, but also, due to the disassembly and modification of the heat pump air - conditioning system, the amount of liquid refrigerant entering the oil circulation rate tester is not completely consistent, affecting the accuracy of the test result of the oil circulation rate.

[0005] Second, increase the number of oil circulation rate testers in the heat pump air - conditioning system, but this method will increase the production and manufacturing cost of the heat pump air - conditioning system. Summary of the Invention

[0006] The purpose of the present invention is to provide an oil circulation rate testing device and method for a heat pump air - conditioning system to solve the problems of the existing two methods for testing the oil circulation rate of heat pump air - conditioning systems. One method increases the workload of pipeline disassembly and assembly, and in addition, due to the disassembly and modification of the heat pump air - conditioning system, the amount of liquid refrigerant entering the oil circulation rate tester is not completely consistent, affecting the accuracy of the test results, and the other method increases the production and manufacturing cost of the heat pump air - conditioning system.

[0007] To achieve this purpose, the present invention adopts the following technical solutions:

[0008] An oil circulation rate testing device for a heat pump air-conditioning system, which is used to test the oil circulation rate of the heat pump air-conditioning system. The heat pump air-conditioning system includes a compressor, a four-way valve, a first heat exchanger, a second heat exchanger and an expansion valve. The output end of the compressor is connected to the first end of the four-way valve. The second end of the four-way valve is connected to the first end of the first heat exchanger. The second end of the first heat exchanger is connected to the first end of the expansion valve. The second end of the expansion valve is connected to the first end of the second heat exchanger. The second end of the second heat exchanger is connected to the third end of the four-way valve. The fourth end of the four-way valve is connected to the input end of the compressor;

[0009] The oil circulation rate testing device for the heat pump air-conditioning system includes:

[0010] A tester and a control valve group. The tester and the control valve group are both arranged on the connecting pipeline between the first heat exchanger and the second heat exchanger. The tester is used to measure the value of the oil circulation rate in the refrigerant. The control valve group includes a plurality of solenoid valves. The heat pump air-conditioning system is configured with a refrigeration condition testing mode, a heating condition testing mode and an offline mode;

[0011] In the refrigeration condition testing mode, the control valve group can sequentially connect the second end of the first heat exchanger, the input end of the tester, the output end of the tester, the first end of the expansion valve, the second end of the expansion valve and the first end of the second heat exchanger; In the heating condition testing mode, the control valve group can sequentially connect the first end of the second heat exchanger, the input end of the tester, the output end of the tester, the second end of the expansion valve, the first end of the expansion valve and the second end of the first heat exchanger; In the offline mode, the control valve group can sequentially connect the second end of the first heat exchanger, the first end of the expansion valve, the second end of the expansion valve and the first end of the second heat exchanger, and can cut off the connection between the first heat exchanger, the tester and the second heat exchanger.

[0012] Preferably, the control valve group includes a first valve group, a second valve group and a third valve group, and the first valve group, the second valve group and the third valve group are all configured with three ports. The first end of the first valve group is connected to the second end of the first heat exchanger. The second end of the first valve group is connected to the first end of the expansion valve. The third end of the first valve group is connected to the input end of the tester; The first end of the second valve group is connected to the first end of the second heat exchanger. The second end of the second valve group is connected to the second end of the expansion valve. The third end of the second valve group is connected to the input end of the tester; The first end of the third valve group is connected to the output end of the tester. The second end of the third valve group is connected to the first end of the expansion valve. The third end of the third valve group is connected to the second end of the expansion valve.

[0013] Preferably, the first valve group includes a first solenoid valve and a second solenoid valve. One end of the first solenoid valve and one end of the second solenoid valve are both connected to the second end of the first heat exchanger. The other end of the first solenoid valve is connected to the first end of the expansion valve, and the other end of the second solenoid valve is connected to the input end of the tester.

[0014] Preferably, the second valve group includes a third solenoid valve and a fourth solenoid valve. One end of the third solenoid valve and one end of the fourth solenoid valve are both connected to the first end of the second heat exchanger. The other end of the fourth solenoid valve is connected to the input end of the tester, and the other end of the third solenoid valve is connected to the second end of the expansion valve.

[0015] Preferably, the third valve group includes a fifth solenoid valve and a sixth solenoid valve. One end of the fifth solenoid valve and one end of the sixth solenoid valve are both connected to the output end of the tester. The other end of the fifth solenoid valve is connected to the first end of the expansion valve, and the other end of the sixth solenoid valve is connected to the second end of the expansion valve.

[0016] Preferably, the control valve group includes a first three-way valve, a second three-way valve, and a third three-way valve. The three ports of the first three-way valve are respectively connected to the second end of the first heat exchanger, the input end of the tester, and the first end of the expansion valve. The three ports of the second three-way valve are respectively connected to the first end of the second heat exchanger, the input end of the tester, and the second end of the expansion valve. The three ports of the third three-way valve are respectively connected to the output end of the tester, the first end of the expansion valve, and the second end of the expansion valve.

[0017] Preferably, the oil circulation rate testing device of the heat pump air-conditioning system further includes a controller. The four-way valve is an electromagnetic four-way reversing valve, and both the electromagnetic four-way reversing valve and the control valve group are electrically connected to the controller.

[0018] An oil circulation rate testing method for a heat pump air-conditioning system, which is applied to the oil circulation rate testing device of the above heat pump air-conditioning system. The oil circulation rate testing device of the heat pump air-conditioning system further includes a controller. The four-way valve is an electromagnetic four-way reversing valve, and both the electromagnetic four-way reversing valve and the control valve group are electrically connected to the controller. The oil circulation rate testing method for the heat pump air-conditioning system specifically includes the following steps:

[0019] S100. Determine whether it is necessary to test the oil circulation rate of the heat pump air-conditioning system. If not, proceed to step S200;

[0020] S200. Determine the operating condition of the heat pump air-conditioning system. If it is in the cooling condition, proceed to step S201; if it is in the heating condition, proceed to step S202;

[0021] S201. Control the control valve group to sequentially connect the second end of the first heat exchanger, the input end of the tester, the output end of the tester, the first end of the expansion valve, the second end of the expansion valve, and the first end of the second heat exchanger;

[0022] S202. Control the control valve group to sequentially connect the first end of the second heat exchanger, the input end of the tester, the output end of the tester, the second end of the expansion valve, the first end of the expansion valve, and the second end of the first heat exchanger.

[0023] Preferably, the specific method for judging the operating condition of the heat pump air-conditioning system is as follows:

[0024] Judge the connection state of the four ports of the electromagnetic four-way reversing valve. If the first end of the electromagnetic four-way reversing valve is connected to the second end of the electromagnetic four-way reversing valve, the heat pump air-conditioning system is in the refrigeration operating condition; if the first end of the electromagnetic four-way reversing valve is connected to the third end of the electromagnetic four-way reversing valve, the heat pump air-conditioning system is in the heating operating condition.

[0025] Preferably, judging whether it is necessary to test the oil circulation rate of the heat pump air-conditioning system further includes the following steps:

[0026] If not, control the control valve group to sequentially connect the second end of the first heat exchanger, the first end of the expansion valve, the second end of the expansion valve, and the first end of the second heat exchanger, and control the control valve group to cut off the connection between the second end of the first heat exchanger, the tester, and the first end of the second heat exchanger.

[0027] The beneficial effects of the present invention are:

[0028] The present invention provides an oil circulation rate testing device and method for a heat pump air-conditioning system. The oil circulation rate testing device for the heat pump air-conditioning system includes a tester and a control valve group. Among them, both the tester and the control valve group are arranged on the connecting pipeline between the first heat exchanger and the second heat exchanger. The tester is used to measure the value of the oil circulation rate in the refrigerant. The control valve group includes a plurality of solenoid valves. The oil circulation rate testing device of the heat pump air-conditioning system is configured with a refrigeration condition testing mode, a heating condition testing mode, and an offline mode. In the refrigeration condition testing mode, the second end of the first heat exchanger, the input end of the tester, the output end of the tester, the first end of the expansion valve, the second end of the expansion valve, and the first end of the second heat exchanger are sequentially connected through the control valve group. Since the first heat exchanger is a condenser under the refrigeration condition, it can ensure that the liquid refrigerant flowing out of the condenser enters the tester. In the heating condition testing mode, the first end of the second heat exchanger, the input end of the tester, the output end of the tester, the second end of the expansion valve, the first end of the expansion valve, and the second end of the first heat exchanger are sequentially connected through the control valve group. Since the second heat exchanger is a condenser under the heating condition, it can ensure that the liquid refrigerant flowing out of the condenser also enters the tester under the heating condition. In the offline mode, the second end of the first heat exchanger, the first end of the expansion valve, the second end of the expansion valve, and the first end of the second heat exchanger are sequentially connected through the control valve group, and the connection between the first heat exchanger, the tester, and the second heat exchanger is cut off. At this time, the liquid refrigerant will no longer enter the tester. Thus, the control valve group can switch the flow direction of the refrigerant under different conditions of the heat pump air-conditioning system, ensuring that under the refrigeration and heating conditions, the refrigerant flows from the output end of the condenser into the input end of the tester, ensuring the consistency of the oil circulation rate test under the refrigeration and heating conditions of the heat pump air-conditioning system, and there is no need to remove the tester, change its direction, and then reinstall it into the system, nor is it necessary to increase the number of testers. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic diagram of an oil circulation rate testing device for a heat pump air-conditioning system provided in Embodiment 1 of the present invention;

[0030] Figure 2 is a schematic diagram of an oil circulation rate testing device for a heat pump air-conditioning system provided in Embodiment 2 of the present invention.

[0031] In the figure:

[0032] 101, compressor; 102, four-way valve; 103, first heat exchanger; 104, second heat exchanger; 105, expansion valve;

[0033] 1, tester;

[0034] 21. First valve group; 211. First magnetic valve; 212. Second magnetic valve; 22. Second valve group; 221. Third magnetic valve; 222. Fourth magnetic valve; 23. Third valve group; 231. Fifth magnetic valve; 232. Sixth magnetic valve; 24. First three-way valve; 25. Second three-way valve; 26. Third three-way valve. Detailed implementation mode

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that for the sake of description, only parts related to the present invention are shown in the drawings, rather than all structures.

[0036] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0037] In the present invention, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "over", and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "under", and "beneath" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the horizontal height of the first feature is lower than that of the second feature.

[0038] In the description of this embodiment, the orientation or positional relationships such as "above", "below", "right", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention. In addition, the terms "first" and "second" are only used for distinction in description and have no special meanings.

[0039] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation of the present invention.

[0040] Embodiment 1

[0041] As Figure 1 shown, Embodiment 1 of the present invention provides an oil circulation rate test device for a heat pump air-conditioning system, which is used to test the oil circulation rate of the heat pump air-conditioning system. Specifically, the heat pump air-conditioning system includes a compressor 101, a four-way valve 102, a first heat exchanger 103, a second heat exchanger 104, and an expansion valve 105. The output end of the compressor 101 is connected to the first end of the four-way valve 102. The second end of the four-way valve 102 is connected to the first end of the first heat exchanger 103. The second end of the first heat exchanger 103 is connected to the first end of the expansion valve 105. The second end of the expansion valve 105 is connected to the first end of the second heat exchanger 104. The second end of the second heat exchanger 104 is connected to the third end of the four-way valve 102. The fourth end of the four-way valve 102 is connected to the input end of the compressor 101.

[0042] Specifically, as Figure 1 shown, the heat pump air-conditioning system is configured with a refrigeration mode and a heating mode. In the refrigeration mode, the refrigerant discharged from the output end of the compressor 101 sequentially passes through the first end of the four-way valve 102, the second end of the four-way valve 102, the first heat exchanger 103, the expansion valve 105, the second heat exchanger 104, the third end of the four-way valve 102, the fourth end of the four-way valve 102, and the input end of the compressor 101 and then returns to the compressor 101 to complete a cycle of the refrigerant. In the refrigeration mode, the first heat exchanger 103 is a condenser, and the refrigerant dissipates heat and condenses through the first heat exchanger 103. The second heat exchanger 104 is an evaporator, and the refrigerant absorbs heat and heats up through the second heat exchanger 104. In the heating mode, the refrigerant discharged from the output end of the compressor 101 sequentially passes through the first end of the four-way valve 102, the third end of the four-way valve 102, the second heat exchanger 104, the expansion valve 105, the first heat exchanger 103, the second end of the four-way valve 102, the fourth end of the four-way valve 102, and the input end of the compressor 101 and then returns to the compressor 101 to complete a cycle of the refrigerant. In the heating mode, the second heat exchanger 104 is a condenser, and the refrigerant dissipates heat and condenses through the second heat exchanger 104. The first heat exchanger 103 is an evaporator, and the refrigerant absorbs heat and heats up through the first heat exchanger 103. It should be noted that the expansion valve 105 is a two-way expansion valve 105, which can adjust the refrigerant flow rate supplied to the evaporator both forward and backward to ensure the superheat of the evaporator.

[0043] Specifically, as Figure 1As shown in the figure, the oil circulation rate test device of the heat pump air-conditioning system includes a tester 1 and a control valve group. Among them, the tester 1 and the control valve group are both arranged on the connecting pipeline between the first heat exchanger 103 and the second heat exchanger 104. The tester 1 is used to measure the value of the oil circulation rate in the refrigerant. The control valve group includes a plurality of solenoid valves. The heat pump air-conditioning system is configured with a refrigeration working condition test mode, a heating working condition test mode, and an offline mode. In the refrigeration working condition test mode, the control valve group can connect the second end of the first heat exchanger 103, the input end of the tester 1, the output end of the tester 1, the first end of the expansion valve 105, the second end of the expansion valve 105, and the first end of the second heat exchanger 104 in sequence; in the heating working condition test mode, the control valve group can connect the first end of the second heat exchanger 104, the input end of the tester 1, the output end of the tester 1, the second end of the expansion valve 105, the first end of the expansion valve 105, and the second end of the first heat exchanger 103 in sequence; in the offline mode, the control valve group can connect the second end of the first heat exchanger 103, the expansion valve 105, and the first end of the second heat exchanger 104 in sequence, and can cut off the connection between the first heat exchanger 103, the tester 1, and the second heat exchanger 104.

[0044] Specifically, as Figure 1As shown, when testing the oil circulation rate of the heat pump air-conditioning system under the refrigeration condition, the second end of the first heat exchanger 103, the input end of the tester 1, the output end of the tester 1, the first end of the expansion valve 105, the second end of the expansion valve 105, and the first end of the second heat exchanger 104 are connected in sequence through the control valve group. Since the first heat exchanger 103 is a condenser under the refrigeration condition, it can ensure that the liquid refrigerant flowing out of the condenser enters the tester 1; when the heat pump air-conditioning system is switched to the heating condition to test the oil circulation rate, the first end of the second heat exchanger 104, the input end of the tester 1, the output end of the tester 1, the second end of the expansion valve 105, the first end of the expansion valve 105, and the second end of the first heat exchanger 103 are connected in sequence through the control valve group. Since the second heat exchanger 104 is a condenser under the heating condition, it can ensure that the liquid refrigerant flowing out of the condenser also enters the tester 1 under the heating condition; when it is not necessary to test the oil circulation rate of the heat pump air-conditioning system, the second end of the first heat exchanger 103, the first end of the expansion valve 105, the second end of the expansion valve 105, and the first end of the second heat exchanger 104 are connected in sequence through the control valve group, and the connection between the first heat exchanger 103, the tester 1, and the second heat exchanger 104 is cut off. At this time, the liquid refrigerant will no longer enter the tester 1. Thus, the control valve group can switch the flow direction of the refrigerant under different conditions of the heat pump air-conditioning system, ensuring that the refrigerant flows from the output end of the condenser to the input end of the tester 1 under both the refrigeration and heating conditions, ensuring the consistency of the oil circulation rate test under the refrigeration and heating conditions of the heat pump air-conditioning system, and eliminating the need to remove the tester 1, reverse its direction, and reinstall it into the system, nor the need to increase the number of testers 1.

[0045] Specifically, as Figure 1As shown in the figure, in this embodiment, the control valve group includes a first valve group 21, a second valve group 22, and a third valve group 23. The first valve group 21, the second valve group 22, and the third valve group 23 are all configured with three ports. The first end of the first valve group 21 is connected to the second end of the first heat exchanger 103, the second end of the first valve group 21 is connected to the first end of the expansion valve 105, and the third end of the first valve group 21 is connected to the input end of the tester 1. The first end of the second valve group 22 is connected to the first end of the second heat exchanger 104, the second end of the second valve group 22 is connected to the second end of the expansion valve 105, and the third end of the second valve group 22 is connected to the input end of the tester 1. The first end of the third valve group 23 is connected to the output end of the tester 1, the second end of the third valve group 23 is connected to the first end of the expansion valve 105, and the third end of the third valve group 23 is connected to the second end of the expansion valve 105. Specifically, through the first valve group 21, the second end of the first heat exchanger 103 can be selectively connected to the input end of the tester 1 or the first end of the expansion valve 105; through the second valve group 22, the first end of the second heat exchanger 104 can be selectively connected to the input end of the tester 1 or the second end of the expansion valve 105; through the third valve group 23, the output end of the tester 1 can be selectively connected to the first end of the expansion valve 105 or the second end of the expansion valve 105.

[0046] More specifically, as Figure 1 shown in the figure, the first valve group 21 includes a first solenoid valve 211 and a second solenoid valve 212. One end of the first solenoid valve 211 and one end of the second solenoid valve 212 are both connected to the second end of the first heat exchanger 103. The other end of the first solenoid valve 211 is connected to the first end of the expansion valve 105, and the other end of the second solenoid valve 212 is connected to the input end of the tester 1. The second valve group 22 includes a third solenoid valve 221 and a fourth solenoid valve 222. One end of the third solenoid valve 221 and one end of the fourth solenoid valve 222 are both connected to the first end of the second heat exchanger 104. The other end of the fourth solenoid valve 222 is connected to the input end of the tester 1, and the other end of the third solenoid valve 221 is connected to the second end of the expansion valve 105. The third valve group 23 includes a fifth solenoid valve 231 and a sixth solenoid valve 232. One end of the fifth solenoid valve 231 and one end of the sixth solenoid valve 232 are both connected to the output end of the tester 1. The other end of the fifth solenoid valve 231 is connected to the first end of the expansion valve 105, and the other end of the sixth solenoid valve 232 is connected to the second end of the expansion valve 105.

[0047] Specifically, in the refrigeration operating condition test mode, the first heat exchanger 103 serves as a condenser, and the second heat exchanger 104 serves as an evaporator. Therefore, it is necessary to connect the second end of the first heat exchanger 103 to the input end of the tester 1. At this time, the specific operating states of the first valve group 21, the second valve group 22, and the third valve group 23 are as follows: the first solenoid valve 211 is closed, the second solenoid valve 212 is open, and the refrigerant enters the tester 1 from the second end of the first heat exchanger 103; the third solenoid valve 221 is open, the fourth solenoid valve 222 is closed, the fifth solenoid valve 231 is open, and the sixth solenoid valve 232 is closed. Thus, the refrigerant flowing out of the tester 1 sequentially flows through the first end of the expansion valve 105, the second end of the expansion valve 105, and the first end of the second heat exchanger 104. In the heating operating condition test mode, the second heat exchanger 104 serves as a condenser, and the first heat exchanger 103 serves as an evaporator. Therefore, it is necessary to connect the first end of the second heat exchanger 104 to the input end of the tester 1. At this time, the specific operating states of the first valve group 21, the second valve group 22, and the third valve group 23 are as follows: the third solenoid valve 221 is closed, the fourth solenoid valve 222 is open, and the refrigerant enters the tester 1 from the first end of the second heat exchanger 104; the first solenoid valve 211 is open, the second solenoid valve 212 is closed, the fifth solenoid valve 231 is closed, and the sixth solenoid valve 232 is open. Thus, the refrigerant flowing out of the tester 1 sequentially flows through the second end of the expansion valve 105, the first end of the expansion valve 105, and the second end of the first heat exchanger 103. In the offline mode, the specific operating states of the first valve group 21, the second valve group 22, and the third valve group 23 are as follows: the first solenoid valve 211 is open, the second solenoid valve 212 is closed, the third solenoid valve 221 is open, the fourth solenoid valve 222 is closed, the fifth solenoid valve 231 is closed, and the sixth solenoid valve 232 is closed. Thus, the second end of the first heat exchanger 103, the expansion valve 105, and the first end of the second heat exchanger 104 are sequentially connected. Thus, by controlling the opening and closing states of the first solenoid valve 211, the second solenoid valve 212, the third solenoid valve 221, the fourth solenoid valve 222, the fifth solenoid valve 231, and the sixth solenoid valve 232, the switching of the oil circulation rate test device of the heat pump air-conditioning system among the refrigeration operating condition test mode, the heating operating condition test mode, and the offline mode is effectively achieved.

[0048] Preferably, the oil circulation rate test device of the heat pump air-conditioning system further includes a controller. The four-way valve 102 is an electromagnetic four-way reversing valve. Both the control valve group and the electromagnetic four-way reversing valve are electrically connected to the controller. The controller can control the working state of the electromagnetic four-way reversing valve to switch the heat pump air-conditioning system between the refrigeration working condition and the heating working condition. The controller can also control the working state of the control valve group to switch the oil circulation rate test device of the heat pump air-conditioning system between the refrigeration working condition test mode, the heating working condition test mode, and the offline mode. Specifically, when it is necessary to test the oil circulation rate of the heat pump air-conditioning system, the controller monitors the connection relationship of the four ports of the electromagnetic four-way reversing valve in real time, and controls the working state of the control valve group according to the connection relationship of the electromagnetic four-way reversing valve, so as to selectively switch the oil circulation rate test device of the heat pump air-conditioning system to the refrigeration working condition test mode or the heating working condition test mode.

[0049] Embodiment 2

[0050] To avoid redundancy, only the different features from Embodiment 1 will be introduced in this embodiment. Specifically, as Figure 2 shown in, the control valve group includes a first three-way valve 24, a second three-way valve 25, and a third three-way valve 26. The three ports of the first three-way valve 24 are respectively connected to the second end of the first heat exchanger 103, the input end of the tester 1, and the first end of the expansion valve 105. The three ports of the second three-way valve 25 are respectively connected to the first end of the second heat exchanger 104, the input end of the tester 1, and the second end of the expansion valve 105. The three ports of the third three-way valve 26 are respectively connected to the output end of the tester 1, the first end of the expansion valve 105, and the second end of the expansion valve 105. In this embodiment, by setting three three-way valves, the same functions as the first valve group 21, the second valve group 22, and the third valve group 23 in Embodiment 1 can be achieved, and compared with Embodiment 1, the number of solenoid valves used is less, which is more conducive to the connection and arrangement of circuits and subsequent fault maintenance. Of course, in other embodiments, the control valve group can also have other options, as long as it can ensure that the input end of the tester 1 is connected to the output end of the condenser when the working condition of the heat pump air-conditioning system changes.

[0051] Embodiment 3

[0052] Embodiment 3 of the present invention provides an oil circulation rate test method for a heat pump air-conditioning system, which is applied to the oil circulation rate test device of the heat pump air-conditioning system described above. The oil circulation rate test method for the heat pump air-conditioning system specifically includes the following steps:

[0053] S100. Determine whether it is necessary to test the oil circulation rate of the heat pump air-conditioning system. If so, proceed to step S200.

[0054] Specifically, determining whether it is necessary to test the oil circulation rate of the heat pump air conditioning system further includes the following steps: If not, control the control valve group to connect the second end of the first heat exchanger 103, the expansion valve 105, and the first end of the second heat exchanger 104 in sequence, and control the control valve group to cut off the connection between the first end of the first heat exchanger 103, the tester 1, and the first end of the second heat exchanger 104.

[0055] Optionally, the working state of the control valve group can be changed periodically by the controller, so as to test the oil circulation rate of the heat pump air conditioning system periodically. Optionally, the heat pump air conditioning system further includes an instruction input terminal, which is electrically connected to the controller, and the staff can input an instruction to test the oil circulation rate of the heat pump air conditioning system through the instruction input terminal. Further optionally, when the heat pump air conditioning system is applied to a vehicle, the instruction input terminal can be the central control screen of the vehicle.

[0056] S200. Determine the working condition of the heat pump air conditioning system. If it is in the cooling working condition, proceed to step S201; if it is in the heating working condition, proceed to step S202.

[0057] S201. Control the control valve group to connect the second end of the first heat exchanger 103, the input end of the tester 1, the output end of the tester 1, the first end of the expansion valve 105, the second end of the expansion valve 105, and the first end of the second heat exchanger 104 in sequence.

[0058] S202. Control the control valve group to connect the first end of the second heat exchanger 104, the input end of the tester 1, the output end of the tester 1, the second end of the expansion valve 105, the first end of the expansion valve 105, and the second end of the first heat exchanger 103 in sequence.

[0059] Specifically, the specific method for determining the working condition of the heat pump air conditioning system is: Determine the connection state of the four ports of the electromagnetic four-way reversing valve. If the first end of the electromagnetic four-way reversing valve is connected to the second end of the electromagnetic four-way reversing valve, the heat pump air conditioning system is in the cooling working condition; if the first end of the electromagnetic four-way reversing valve is connected to the third end of the electromagnetic four-way reversing valve, the heat pump air conditioning system is in the heating working condition. With such a setting, it is possible to accurately and quickly switch the oil circulation rate test device of the heat pump air conditioning system between the cooling working condition test mode and the heating working condition test mode according to the connection relationship of the electromagnetic four-way reversing valve, ensuring the accuracy and reliability of the oil circulation rate test results.

[0060] Therefore, applying the oil circulation rate test method of the heat pump air-conditioning system to the oil circulation rate test device of the heat pump air-conditioning system can ensure that under the refrigeration condition and the heating condition of the heat pump air-conditioning system, the refrigerant flows into the input end of the tester 1 in a liquid state from the output end of the condenser, ensuring the accuracy of the tester 1, ensuring the accuracy of the tested oil circulation rate of the heat pump air-conditioning system under the refrigeration and heating conditions, and eliminating the need to remove the tester 1, reverse its direction and reinstall it into the system, as well as the need to increase the number of testers 1.

[0061] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the claims of the present invention.

Claims

1. An oil circulation rate testing device for a heat pump air-conditioning system, which is used to test the oil circulation rate of the heat pump air-conditioning system. The heat pump air-conditioning system includes a compressor (101), a four-way valve (102), a first heat exchanger (103), a second heat exchanger (104) and an expansion valve (105). The output end of the compressor (101) is connected to the first end of the four-way valve (102). The second end of the four-way valve (102) is connected to the first end of the first heat exchanger (103). The second end of the first heat exchanger (103) is connected to the first end of the expansion valve (105). The second end of the expansion valve (105) is connected to the first end of the second heat exchanger (104). The second end of the second heat exchanger (104) is connected to the third end of the four-way valve (102). The fourth end of the four-way valve (102) is connected to the input end of the compressor (101); It is characterized in that The oil circulation rate testing device for the heat pump air-conditioning system includes: A tester (1) and a control valve group. The tester (1) and the control valve group are both arranged on the connecting pipeline between the first heat exchanger (103) and the second heat exchanger (104). The tester (1) is used to measure the value of the oil circulation rate in the refrigerant. The control valve group includes a plurality of solenoid valves. The oil circulation rate testing device for the heat pump air-conditioning system is configured with a refrigeration working condition testing mode, a heating working condition testing mode and an offline mode; In the refrigeration working condition testing mode, the control valve group can connect the second end of the first heat exchanger (103), the input end of the tester (1), the output end of the tester (1), the first end of the expansion valve (105), the second end of the expansion valve (105) and the first end of the second heat exchanger (104) in sequence; In the heating working condition testing mode, the control valve group can connect the first end of the second heat exchanger (104), the input end of the tester (1), the output end of the tester (1), the second end of the expansion valve (105), the first end of the expansion valve (105) and the second end of the first heat exchanger (103) in sequence; In the offline mode, the control valve group can connect the second end of the first heat exchanger (103), the first end of the expansion valve (105), the second end of the expansion valve (105) and the first end of the second heat exchanger (104) in sequence, and can cut off the connection between the first heat exchanger (103), the tester (1) and the second heat exchanger (104).

2. The oil circulation rate testing device for a heat pump air conditioning system according to claim 1, characterized in that, The control valve group includes a first valve group (21), a second valve group (22), and a third valve group (23), and the first valve group (21), the second valve group (22), and the third valve group (23) are each configured with three ports. The first end of the first valve group (21) is connected to the second end of the first heat exchanger (103), the second end of the first valve group (21) is connected to the first end of the expansion valve (105), and the third end of the first valve group (21) is connected to the input end of the tester (1); the first end of the second valve group (22) is connected to the first end of the second heat exchanger (104), the second end of the second valve group (22) is connected to the second end of the expansion valve (105), and the third end of the second valve group (22) is connected to the input end of the tester (1); the first end of the third valve group (23) is connected to the output end of the tester (1), the second end of the third valve group (23) is connected to the first end of the expansion valve (105), and the third end of the third valve group (23) is connected to the second end of the expansion valve (105).

3. The oil circulation rate testing device for a heat pump air-conditioning system according to claim 2, wherein The first valve group (21) includes a first magnetic valve (211) and a second magnetic valve (212). One end of the first magnetic valve (211) and one end of the second magnetic valve (212) are both connected to the second end of the first heat exchanger (103). The other end of the first magnetic valve (211) is connected to the first end of the expansion valve (105), and the other end of the second magnetic valve (212) is connected to the input end of the tester (1).

4. The oil circulation rate testing device for a heat pump air-conditioning system according to claim 2, characterized in that, The second valve group (22) includes a third magnetic valve (221) and a fourth magnetic valve (222). One end of the third magnetic valve (221) and one end of the fourth magnetic valve (222) are both connected to the first end of the second heat exchanger (104). The other end of the fourth magnetic valve (222) is connected to the input end of the tester (1), and the other end of the third magnetic valve (221) is connected to the second end of the expansion valve (105).

5. The oil circulation rate testing device for a heat pump air conditioning system according to claim 2, characterized in that The third valve group (23) includes a fifth magnetic valve (231) and a sixth magnetic valve (232). One end of the fifth magnetic valve (231) and one end of the sixth magnetic valve (232) are both connected to the output end of the tester (1). The other end of the fifth magnetic valve (231) is connected to the first end of the expansion valve (105), and the other end of the sixth magnetic valve (232) is connected to the second end of the expansion valve (105).

6. The oil circulation rate testing device for a heat pump air conditioning system according to claim 1, characterized in that, The control valve group includes a first three-way valve (24), a second three-way valve (25), and a third three-way valve (26). The three ports of the first three-way valve (24) are respectively connected to the second end of the first heat exchanger (103), the input end of the tester (1), and the first end of the expansion valve (105). The three ports of the second three-way valve (25) are respectively connected to the first end of the second heat exchanger (104), the input end of the tester (1), and the second end of the expansion valve (105). The three ports of the third three-way valve (26) are respectively connected to the output end of the tester (1), the first end of the expansion valve (105), and the second end of the expansion valve (105).

7. An oil circulation rate testing device for a heat pump air-conditioning system according to any one of claims 1-6, characterized in that, The oil circulation rate testing device of the heat pump air-conditioning system further includes a controller. The four-way valve (102) is an electromagnetic four-way reversing valve. The electromagnetic four-way reversing valve and the control valve group are both electrically connected to the controller.

8. A method for testing the oil circulation rate of a heat pump air conditioning system, characterized in that, Applied to the oil circulation rate testing device of the heat pump air-conditioning system according to any one of claims 1-7, the oil circulation rate testing device of the heat pump air-conditioning system further includes a controller. The four-way valve (102) is an electromagnetic four-way reversing valve. The electromagnetic four-way reversing valve and the control valve group are both electrically connected to the controller. The oil circulation rate testing method of the heat pump air-conditioning system specifically includes the following steps: S100. Determine whether it is necessary to test the oil circulation rate of the heat pump air-conditioning system. If so, proceed to step S200; S200. Determine the operating condition of the heat pump air-conditioning system. If it is in the cooling condition, proceed to step S201. If it is in the heating condition, proceed to step S202; S201. Control the control valve group to sequentially connect the second end of the first heat exchanger (103), the input end of the tester (1), the output end of the tester (1), the first end of the expansion valve (105), the second end of the expansion valve (105), and the first end of the second heat exchanger (104); S202. Control the control valve group to sequentially connect the first end of the second heat exchanger (104), the input end of the tester (1), the output end of the tester (1), the second end of the expansion valve (105), the first end of the expansion valve (105), and the second end of the first heat exchanger (103).

9. A method for testing the oil circulation rate of a heat pump air conditioning system according to claim 8, characterized in that The specific method for determining the operating condition of the heat pump air-conditioning system is: Determine the connection state of the four ports of the electromagnetic four-way reversing valve. If the first end of the electromagnetic four-way reversing valve is connected to the second end of the electromagnetic four-way reversing valve, the heat pump air-conditioning system is in the cooling condition. If the first end of the electromagnetic four-way reversing valve is connected to the third end of the electromagnetic four-way reversing valve, the heat pump air-conditioning system is in the heating condition.

10. A method for testing the oil circulation rate of a heat pump air conditioning system according to claim 8, characterized in that, Determining whether it is necessary to test the oil circulation rate of the heat pump air-conditioning system also includes the following steps: If not, control the control valve group to connect the second end of the first heat exchanger (103), the first end of the expansion valve (105), the second end of the expansion valve (105), and the first end of the second heat exchanger (104) in sequence, and control the control valve group to cut off the connection between the second end of the first heat exchanger (103), the tester (1), and the first end of the second heat exchanger (104).

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