A welding leak detection device and method for a refrigerator

Abstract

The application provides a welding leakage and welding blockage detection device and method for a refrigerator. The welding leakage and welding blockage detection device comprises: a gas source interface; a first detection pipeline; a second detection pipeline; a gas flow switching valve group; a measurement assembly arranged on the first detection pipeline and the second detection pipeline to obtain the gas flow and gas pressure of a first gas outlet end of the first detection pipeline and the gas flow and gas pressure of a second gas outlet end of the second detection pipeline; and a processor used for determining whether the target pipe section of the refrigeration circuit exists welding leakage and welding blockage according to the flow difference value of the detection gas between the first gas outlet end of the first detection pipeline and the second gas outlet end of the second detection pipeline and / or the gas pressure value of the first detection pipeline or the second detection pipeline. The application can detect whether the refrigerator system pipeline exists welding leakage and welding blockage in a short time, and saves the evacuation and filling refrigerant cost.

Description

Technical Field

[0001] This invention relates to the field of refrigeration equipment, and in particular to a device and method for detecting weld leaks and weld plugs in refrigerators. Background Technology

[0002] During the welding process, leaks and blockages may occur in the pipes inside a refrigerator. A leak refers to a component's solder joint not being properly welded, while a blockage occurs when molten solder flows into the pipe and causes a blockage. However, leaks and blockages in refrigerator pipes often go undetected because the high temperature after the refrigerator's foaming process gradually decreases during its flow on the production line. This means that the room temperature drop measured during the power-on process may appear acceptable, thus failing to detect the problem in time. However, refrigerators with leaks will experience refrigerant leakage during use, leading to poor or no cooling. Refrigerators with blockages will experience refrigerant malfunctions, preventing proper circulation within the system pipes and ultimately causing the compressor to burn out.

[0003] Currently, ultrasonic instruments are commonly used to detect defects such as cracks in pipe welds, thereby determining whether there are weld leaks or blockages in the refrigerator's piping. However, ultrasonic instruments are quite precise, and refrigerators have many weld points. Detecting each weld point would require a significant amount of manpower and resources, and ultrasonic detection is not suitable for assembly line use. Summary of the Invention

[0004] One object of the present invention is to provide a device and method for detecting weld leaks and weld plugs suitable for use in refrigerators, as an alternative to ultrasonic instruments.

[0005] A further objective of this invention is to enable timely detection of weld leaks and blockages in refrigerators.

[0006] Specifically, the present invention provides a weld leak / weld blockage detection device for a refrigerator, the refrigerator including a refrigeration circuit, a filter and a compressor being provided on the refrigeration circuit, and a target pipe section to be detected between the filter and the compressor, the weld leak / weld blockage detection device comprising:

[0007] A gas source interface is used to connect to an external gas source to obtain detection gas from the external gas source;

[0008] The first detection pipeline has a first outlet end connected to the compressor;

[0009] The second detection pipeline has a second air outlet end that is connected to the filter;

[0010] An airflow switching valve assembly is connected to the gas source interface, the first detection pipeline, and the second detection pipeline, and is used to selectively supply the detection gas to the first detection pipeline or the second detection pipeline;

[0011] A measuring component is disposed in the first detection pipeline and the second detection pipeline to obtain the gas flow rate and gas pressure at the first outlet end of the first detection pipeline and the gas flow rate and gas pressure at the second outlet end of the second detection pipeline.

[0012] The processor is configured to determine whether there is a weld leak or blockage in the target pipe section of the refrigeration circuit based on the flow rate difference of the detected gas between the first outlet end of the first detection pipe and the second outlet end of the second detection pipe, and / or the gas pressure value of the first detection pipe or the second detection pipe.

[0013] Furthermore, the refrigeration circuit consists of a first pipe section and a second pipe section. The first pipe section is the pipe section between the compressor and the filter and flows through the evaporator of the refrigerator. The second pipe section is the pipe section between the compressor and the filter and flows through the condenser of the refrigerator.

[0014] The second detection pipeline is configured to open when the target pipeline segment is the first pipeline segment, so that the detection gas enters the first pipeline segment and the second pipeline segment respectively from the filter, so that the detection gas flows to the compressor in the first pipeline segment, and then enters the first detection pipeline from the compressor, and the detection gas is sealed in the second pipeline segment and cannot flow out.

[0015] Furthermore, the processor is configured to determine whether the flow difference is zero when the second detection pipeline is opened, and if the flow difference is zero, determine that there is no weld leak or blockage in the first pipe section; otherwise, continue to determine whether the air pressure value of the first detection pipeline is greater than a preset air pressure value. If the air pressure value is greater than the preset air pressure value, determine that there is no weld leak or blockage in the first pipe section; otherwise, determine that there is a weld leak or blockage in the first pipe section.

[0016] Furthermore, the first detection pipeline is configured to open when the target pipeline segment is the second pipeline segment, so that the detection gas enters the first pipeline segment and the second pipeline segment respectively from the compressor, so that the detection gas flows to the filter in the first pipeline segment and the second pipeline segment, and then enters the second detection pipeline from the filter.

[0017] Furthermore, it also includes a main pipeline for connecting the gas source, the main pipeline connecting the first detection pipeline and the second detection pipeline.

[0018] Furthermore, the main pipeline is equipped with a gas path switching valve, which is configured to allow either the second detection pipeline or the first detection pipeline to be opened.

[0019] Optionally, the gas path switching valve is located at the junction of the main pipeline and the first detection pipeline and the second detection pipeline.

[0020] Furthermore, the main pipeline is equipped with a gas pressure sensor, and the output of the gas pressure sensor is connected to the processor.

[0021] Specifically, the present invention also discloses a method for detecting weld leaks and weld plugs in refrigerators, using the aforementioned weld leak and weld plug detection device, comprising the following steps:

[0022] The flow rate and pressure of the gas at the first outlet of the first detection pipeline of the weld leak and weld plug detection device are obtained, and the flow rate and pressure of the gas at the second outlet of the second detection pipeline of the weld leak and weld plug detection device are also obtained.

[0023] The difference between the flow rate at the first outlet and the flow rate at the second outlet is obtained by subtracting the flow rate at the first outlet and the flow rate at the second outlet.

[0024] The presence of weld leaks or blockages in the target pipe section of the refrigeration circuit is determined based on the flow rate difference of the detected gas between the first outlet end of the first detection pipe and the second outlet end of the second detection pipe, and / or the gas pressure value of the first detection pipe or the second detection pipe.

[0025] Furthermore, the step of subtracting the flow rate value at the first outlet and the flow rate value at the second outlet to obtain the flow rate difference between the first outlet and the second outlet specifically includes the following steps:

[0026] Obtain the first flow difference between the flow rate at the first outlet and the flow rate at the second outlet when the target pipe segment is the first pipe segment; and calculate whether there is a weld leak in the first pipe segment based on the first flow difference.

[0027] Obtain the second flow difference between the flow rate at the first outlet and the flow rate at the second outlet when the target pipe segment is the second pipe segment. Based on the second flow difference and the weld leakage condition of the first pipe segment, calculate whether there is a weld leakage condition in the second pipe segment.

[0028] Furthermore, the step of determining whether there is a weld leak or blockage in the target pipe section of the refrigeration circuit based on the flow rate difference of the detected gas between the first outlet end of the first detection pipe and the second outlet end of the second detection pipe, and / or the gas pressure value of the first detection pipe or the second detection pipe, specifically includes the following steps:

[0029] Compare the air pressure value of the first detection pipeline with the theoretical air pressure value of the first detection pipeline to determine whether there is a weld blockage problem in the first pipeline section;

[0030] Based on the air pressure value of the first detection pipeline when the target pipe section is the first pipe section, and the air pressure values ​​of the first detection pipeline, the second detection pipeline, and the main pipeline when the target pipe section is the second pipe section, the actual pressure outlet value of the second pipe section is calculated. By comparing the actual pressure outlet value of the second pipe section with the theoretical air pressure value, it is determined whether there is a weld blockage problem in the second pipe section.

[0031] The weld leak / blockage detection device disclosed in this invention is designed for refrigerator production lines. It controls the detection gas to enter the refrigeration circuit through a filter or compressor via a first detection pipeline and a second detection pipeline. The processor determines whether there is a weld leak / blockage in the target pipe section of the refrigeration circuit based on the flow rate difference of the detection gas between the first outlet end of the first detection pipeline and the second outlet end of the second detection pipeline, and / or the gas pressure value of the first or second detection pipeline. By connecting the first and second detection pipelines to the corresponding ports of the refrigeration circuit, it is possible to detect whether there is a weld leak / blockage in the refrigerator system pipeline in a short time, saving the cost of vacuuming and refrigerant charging.

[0032] Furthermore, in the weld leak / plug detection device disclosed in this invention, the second detection pipeline is configured to open when the target pipeline segment is the first pipeline segment, so that the detection gas enters the first pipeline segment and the second pipeline segment respectively from the filter, so that the detection gas flows to the compressor in the first pipeline segment, and then enters the first detection pipeline from the compressor, and the detection gas is sealed in the second pipeline segment and cannot flow out. During the opening of the second detection pipeline, by sealing the detection gas in the second pipeline segment and preventing it from flowing out, the influence of the second pipeline segment when the second detection pipeline is ventilated can be minimized as much as possible, so that the second detection pipeline can be used to specifically detect the first detection pipeline when it is ventilated.

[0033] Furthermore, the weld leak / plug detection device disclosed in this invention is also equipped with a gas path switching valve, which facilitates the switching of the gas path between the first detection pipeline and the second detection pipeline, thereby improving detection efficiency.

[0034] The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0035] The following sections will describe some specific embodiments of the invention in detail by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or portions. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0036] Figure 1 This is a schematic diagram illustrating the actual use of a weld leak / plug detection device for a refrigerator according to an embodiment of the present invention.

[0037] Figure 2 yes Figure 1 The diagram shows a schematic structural diagram of a weld leak / plug detection device for refrigerators.

[0038] Figure 3 yes Figure 1 The diagram shows a schematic circuit of the sensor component connecting to the processor in a leak / plug detection device for a refrigerator.

[0039] Figure 4 This is a flowchart of a method for detecting weld leaks and weld plugs in a refrigerator according to an embodiment of the present invention. Detailed Implementation

[0040] Figure 1 This is a schematic structural diagram illustrating the installation of a weld leak / plug detection device for a refrigerator into the refrigeration circuit of a refrigerator according to an embodiment of the present invention. Figure 1 As shown, the refrigeration circuit of the refrigerator includes a compressor 201, a condenser 205, a filter 204, a capillary tube 203, and an evaporator 202 connected in the circuit. The compressor 201 has three pipes: an exhaust pipe, a suction pipe, and a compressor process pipe. The exhaust pipe and suction pipe are used to connect to the refrigeration circuit. The compressor process pipe is used to charge refrigerant during the production or maintenance of the compressor 201. After charging the refrigerant, the end is sealed by gas welding and opened when needed. Therefore, in this embodiment, the compressor process pipe is still in the open state.

[0041] The filter 204 has three pipes: an inlet pipe, an outlet pipe, and a filter process pipe. The inlet pipe and outlet pipe are used to connect to the refrigeration circuit, while the filter process pipe is used to evacuate the filter 204 during production or maintenance. After evacuation, the end is sealed by gas welding and opened when needed. Therefore, in this embodiment, the filter process pipe is still in the open state.

[0042] A typical weld leak / plug detection device includes a gas source interface, a first detection pipeline, a second detection pipeline, an airflow switching valve assembly, and a measuring component. The gas source interface is used to connect to an external gas source to obtain detection gas. The first detection pipeline has a first outlet end connected to a compressor, and the second detection pipeline has a second outlet end connected to a filter. The airflow switching valve assembly is connected to the gas source interface, the first detection pipeline, and the second detection pipeline to selectively supply detection gas to either the first or second detection pipeline. The measuring component is located in the first and second detection pipelines to obtain the gas flow rate and pressure at the first outlet end of the first detection pipeline and the gas flow rate and pressure at the second outlet end of the second detection pipeline. The processor is used to determine whether a target pipe section of the refrigeration circuit has weld leaks or plugs based on the difference in detection gas flow rate between the first outlet end of the first detection pipeline and the second outlet end of the second detection pipeline, and / or the pressure value of the first or second detection pipeline.

[0043] It is understood that the first detection line 101 is connected to the refrigeration circuit through the compressor process pipe, and the second detection line is connected to the refrigeration circuit through the filter process pipe. The weld leak and weld blockage detection device disclosed in this embodiment is designed for refrigerator production lines. It controls the detection gas to enter the refrigeration circuit through the filter 204 or the compressor 201 by controlling the first detection line 101 and the second detection line 102. The processor 7 determines whether there is a weld leak or weld blockage in the target pipe section of the refrigeration circuit based on the flow rate difference of the detection gas between the first outlet end of the first detection line 101 and the second outlet end of the second detection line 102, and / or the gas pressure value of the first detection line 101 or the second detection line 102. Thus, by connecting the first detection line and the second detection line to the corresponding port of the refrigeration circuit, it is possible to detect whether there is a weld leak or weld blockage in the refrigerator system pipes in a short time, saving the cost of vacuuming and refrigerant charging.

[0044] According to an embodiment of the present invention, for the convenience of describing the target pipe section, the refrigeration circuit described above will be described in detail here. The refrigeration circuit includes a compressor 201, a condenser 205, a filter 204, a capillary tube 203, and an evaporator 202 connected in sequence. Since the compressor 201 has an intake valve and an exhaust valve, wherein the exhaust valve of the compressor 201 can prevent gas backflow, the pipeline through the exhaust valve of the compressor 201 cannot flow backward. In the entire refrigeration circuit of the production line, there are two gas exchange ports: the compressor process pipe and the filter process pipe. There are two gas paths from the compressor process pipe to the filter process pipe: the first pipe section and the second pipe section. The first pipe section passes through the compressor process pipe, the compressor 201 suction pipe, the evaporator 202, the capillary tube 203, and the filter 204, finally reaching the filter process pipe. The second pipe section passes through the compressor process pipe, the compressor 201 muffler, the compressor 201 suction valve, the compressor 201 cylinder, the compressor 201 discharge valve, the compressor 201 discharge pipe, the condenser 205, and the filter 204, finally reaching the filter process pipe. The gas flow direction in the first pipe section is reversible, while that in the second pipe section is irreversible.

[0045] According to one embodiment of the present invention, the first detection pipeline 101 and the second detection pipeline 102 use pipe fittings with the same diameter. When the outlet ends of the first detection pipeline 101 and the second detection pipeline 102 are connected to the refrigeration circuit, the gas can pass through the first detection pipeline 101 to the target section of the refrigeration circuit and then be discharged from the second detection pipeline 102, or it can pass through the first detection pipeline 101 to the target section of the refrigeration circuit and then be discharged from the first detection pipeline 101. Therefore, in this embodiment, the first detection pipeline 101 and the second detection pipeline 102 use pipe fittings with the same diameter, so the cross-sectional area of ​​the gas flowing in the pipe fittings is equal. When there is no leakage in the target section, the flow rate is also equal. According to the calculation method of pipeline gas flow rate, it is easy to find that when the gas flow velocity in the first detection pipeline 101 and the gas flow velocity in the second detection pipeline 102 are equal, the gas flow rate in the first detection pipeline 101 and the gas flow rate in the second detection pipeline 102 are equal. Thus, the detection device arranged in the first detection pipeline 101 and the second detection pipeline 102 can calculate the gas flow rate by detecting the gas flow velocity.

[0046] According to one embodiment of the present invention, in order to facilitate the injection of gas into the refrigeration circuit using the first detection line 101 or the second detection line 102, this embodiment also provides a main pipeline 100. One end of the main pipeline 100 is connected to the gas source 1, and the other end of the main pipeline 100 is connected to the first detection line 101 or the second detection line 102, so that the first detection line 101 or the second detection line 102 can obtain airflow from the main pipeline 100 and guide the airflow into the refrigeration circuit. The main pipeline 100 is selectively connected to the first detection line or the second detection line 102, and this connection can be achieved by means of a clamp connection. Specifically, the end of the main pipeline 100 and the first detection pipeline 101 can be connected by a clamp, thereby connecting the main pipeline 100 and the first detection pipeline 101. At this time, the second detection pipeline 102 cannot be connected to the end of the main pipeline 100.

[0047] According to one embodiment of the present invention, in order to selectively connect the main pipeline 100 and the first detection pipeline 101 and the second detection pipeline 102, and to improve the convenience of such connection, the main pipeline 100 and the first detection pipeline 101, and the main pipeline 100 and the second detection pipeline 102 are connected by valves. Thus, when the valve between the main pipeline 100 and the first detection pipeline 101 is open, the valve between the main pipeline 100 and the second detection pipeline 102 can be closed; conversely, when the valve between the main pipeline 100 and the first detection pipeline 101 is closed, the valve between the main pipeline 100 and the second detection pipeline 102 can be opened, thereby enabling selective opening of either the first detection pipeline 101 or the second detection pipeline 102.

[0048] According to one embodiment of the present invention, in order to selectively connect the main pipeline 100 and the first detection pipeline 101, and the main pipeline 100 and the second detection pipeline 102, the end of the main pipeline 100, one end of the first detection pipeline 101, and one end of the second detection pipeline 102 are connected through a gas path switching valve 4. It is understood that the gas path switching valve 4 is a multi-port valve; when two ports of this gas path switching valve 4 are connected, its third port can connect to other ports, thereby connecting the pipeline connected to the third port to the outside. For details, please refer to the prior art, which will not be elaborated here.

[0049] According to one embodiment of the present invention, a pressure sensor 3 is also provided on the main pipeline 100. The pressure sensor 3 is configured to acquire the pressure inside the main pipeline 100. At the same time, a drying filter 2 is also provided on the main pipeline 100. The drying filter 2 is located before the pressure sensor 3 to filter the gas in the gas source 1 connected to the main pipeline 100, thereby reducing impurities in the gas and improving measurement accuracy.

[0050] According to one embodiment of the present invention, a first gas sensor 51 is provided in the first detection pipeline 101, and a second gas sensor 52 is provided in the second detection pipeline 102, thereby enabling direct acquisition of gas flow rate data and gas pressure data. The first gas sensor 51 and the second gas sensor 52 respectively acquire the gas flow rate within their respective pipelines. It is understood that the first gas sensor 51 and the second gas sensor 52 should be of the same model.

[0051] According to one embodiment of the present invention, both the first gas sensor 51 and the second gas sensor 52 are pipeline gas sensors. The pipeline gas sensor calculates the gas flow rate by measuring the airflow velocity, and its output voltage signal is proportional to the airflow velocity. The processor 7 then calculates the specific gas flow rate value based on the voltage signal. It is understood that this type of sensor is typically connected to the pipeline using a threaded connection. In addition to measuring wind speed, the first gas sensor 51 and the second gas sensor 52 also integrate the function of measuring air pressure.

[0052] According to one embodiment of the present invention, the main pipeline 100 and the first detection pipeline 101 and the second detection pipeline 102 have the same diameter, so there is no need to distinguish the pipe diameters selected for the main pipeline 100, the first detection pipeline 101 and the second detection pipeline 102 during the manufacturing process, which facilitates manufacturing. When the main pipeline 100 is connected to the first detection pipeline 101 or the second detection pipeline 102, the gas flow is relatively smooth because the pipe diameters are the same.

[0053] According to one embodiment of the present invention, a first valve 61 is provided at one end of the first detection pipeline 101 connected to the refrigeration circuit (i.e., the first outlet end of the first detection pipeline 101), and a second valve 62 is provided at one end of the second detection pipeline 102 connected to the refrigeration circuit (i.e., the second outlet end of the second detection pipeline 102). The first detection pipeline 101 and the second detection pipeline 102 are connected to the refrigeration pipeline through the valves. More specifically, the first detection pipeline 101 is connected to the compressor process pipe through the valve, and the second detection pipeline 102 is connected to the filter process pipe through the valve. This valve connection method is adopted according to the testing needs of the refrigerator production line. On the refrigerator production line, it is usually necessary to continuously test multiple refrigeration pipelines. By using valves to connect the first detection pipeline 101 to the refrigeration pipeline or the second detection pipeline 102 to the refrigeration pipeline, it is convenient to arrange the batch testing of refrigeration pipelines on the refrigerator production line.

[0054] Specifically, the present invention also discloses a method for detecting weld leaks and weld plugs in refrigerators, using the aforementioned weld leak and weld plug detection device, comprising the following steps:

[0055] S1. Obtain the flow rate and pressure value of the detection gas at the first outlet end of the first detection pipeline of the weld leak / weld plug detection device, and obtain the flow rate and pressure value of the detection gas at the second outlet end of the second detection pipeline of the weld leak / weld plug detection device.

[0056] S2. Subtract the flow rate value at the first outlet from the flow rate value at the second outlet to obtain the flow rate difference between the first outlet and the second outlet.

[0057] S3. Determine whether there is a weld leak or blockage in the target pipe section of the refrigeration circuit based on the flow rate difference of the detected gas between the first outlet end of the first detection pipe and the second outlet end of the second detection pipe, and / or the gas pressure value of the first detection pipe or the second detection pipe.

[0058] According to an embodiment of the present invention, step S1 specifically includes the following steps:

[0059] S11. Obtain the first flow difference between the flow rate at the first outlet and the flow rate at the second outlet when the target pipe segment is the first pipe segment.

[0060] S12. Obtain the second flow difference between the flow rate at the first outlet and the flow rate at the second outlet when the target pipe segment is the second pipe segment.

[0061] According to one embodiment of the present invention, in step S11, in order to obtain only the measurement results of the first pipe section, during the process of the detection gas entering the first pipe section and the second pipe section respectively from the filter 204, a method is adopted to control the introduction time of the detection gas, so that the detection gas is sealed in the second pipe section and cannot flow out, thereby making the gas pressure in the second pipe section reach a state that does not affect the airflow in the first pipe section. Specifically, after the detection gas is introduced into the filter 204, the gas pressure in the second pipe section no longer changes after time point t1, and the gas introduction ends at time point t2. Then, the relevant measurement results at time points t1 to t2 are taken. For example, if the detection gas is introduced into the filter 204 for a total of 4 seconds, then the measurement results between the 2nd second and the 4th second are taken. For ease of comparison, in step S2, the measurement gas is also introduced for the same time, and the relevant measurement results at time points t1 to t2 are also taken.

[0062] According to an embodiment of the present invention, in step S11, when the target pipe segment is the first pipe segment, the main pipe is connected to the second detection pipe 102, the main pipe is connected to the gas source 1, and the gas is supplied to the filter process pipe through the main pipe and the second detection pipe 102. The gas sensor in the first detection pipe 101 monitors the airflow from the compressor process pipe and can detect the welding leakage and welding blockage of the first pipe segment.

[0063] According to an embodiment of the present invention, in step S12, the gas path direction in step S11 is reversed, the main pipe is connected to the first detection pipe 101, and the gas is supplied to the compressor process pipe through the main pipe and the first detection pipe 101. At this time, the first pipe section and the second pipe section are in a connected state. Since the welding leakage and welding blockage of the first pipe section have been determined in step S11, the welding blockage and welding leakage of the second pipe section can be determined by measuring the outflow of the filter process pipe in step S12.

[0064] According to an embodiment of the present invention, step S2 specifically includes the following steps:

[0065] S21. Obtain the first flow difference between the flow rate value at the first outlet and the flow rate value at the second outlet when the target pipe segment is the first pipe segment. Based on the first flow difference, calculate whether there is a weld leak in the first pipe segment.

[0066] S22. Obtain the second flow difference between the flow rate at the first outlet and the flow rate at the second outlet when the target pipe segment is the second pipe segment. Based on the second flow difference and the weld leakage of the first pipe segment, calculate whether there is a weld leakage in the second pipe segment.

[0067] According to one embodiment of the present invention, the weld leakage or blockage of the first detection pipeline 101 and the second detection pipeline 102 can be determined by the difference in gas pressure and flow rate at the gas inlet and outlet (compressor process pipe and filter process pipe). Specifically, if the gas inlet and outlet flow rates are not equal, it is determined that there is a leak in the pipeline; if the gas inlet and outlet flow rates are equal, but the exhaust pressure is different from the normal exhaust pressure of the refrigerator model, it is determined that the refrigerator is blocked; if the gas pressure difference is not large at this time, it is determined to be qualified; if the gas pressure difference is large at this time but there is exhaust at the gas outlet, it is determined to be a partial blockage; if there is no exhaust at the gas outlet, it indicates that a weld blockage has occurred.

[0068] According to one embodiment of the present invention, in performing a specific operation, in step S21, the first detection line 101 is connected to the compressor process line, and the second detection line 102 is connected to the filter process line to begin measurement. First, compressed gas is continuously introduced into the second detection line 102 for 4 seconds, and the flow rate m of the first detection line 101 is measured by the first gas sensor 51. 压缩机1 The flow rate m of the second detection pipeline 102 is measured by the second gas sensor 52. 过滤器1 And the air pressure P of the main pipeline 100 is measured by air pressure sensor 3. 主1 The gas pressure P in the first detection line 101 is measured by the first gas sensor 51. 压缩机1 The gas pressure P in the second detection line 102 is measured by the second gas sensor 52. 过滤器1 Then proceed to step S3, if m 压缩机1 =m 过滤器1 If m 压缩机1 ≠m 过滤器1 If P 压缩机1 >aP 压缩机0 (a is a set value, entered according to on-site process conditions, ranging from 0.8 to 0.95), then it is determined that there is no abnormality in the flow of gas path two. If P 压缩机1 <aP 压缩机0 If the weld blockage is affecting the cooling system, it needs to be repaired. Here, P... 压缩机0 This is a theoretical calculation value, which is related to the supply gas pressure and the refrigerator model. It is obtained through computer simulation calculation, and the specific calculation process is well known to those skilled in the art, so it will not be described in detail here.

[0069] According to one embodiment of the present invention, after step S1 is completed, the gas path switching valve 4 is controlled to execute step S2, in which compressed gas is continuously supplied to the first detection line 101. The gas enters the refrigeration line from the compressor 201 for 4 seconds. During this time, the flow rate m of the first detection line 101 is measured by the first gas sensor 51.压缩机2 The flow rate (m) of the second detection pipeline 102 is measured by the second gas sensor 52. 过滤器2 And the air pressure P of main pipeline 100 is measured by air pressure sensor 3. 主2 The gas pressure P in the first detection line 101 is measured by the first gas sensor 51. 压缩机2 The gas pressure P in the second detection line 102 is measured by the second gas sensor 52. 过滤器2 If m 压缩机2 =m 过滤器2 If the second pipe section is leak-free, it can be inferred that there is no weld leak in the second pipe section at this time; otherwise, if m 压缩机2 ≠m 过滤器2 If so, it is determined that a leak has occurred in the second pipe section. The P obtained from the first test... 压缩机1 and P 压缩机0 This allows us to calculate the approximate pressure drop of the gas supply to the compressor process pipe in the first pipe section. This provides a state parameter for the first pipe section for this calculation, which, combined with the simulation calculation, allows us to obtain the P value of the second pipe section. 压缩机0 The parameter P 压缩机0 The parameter P is related to the supplied gas and the refrigerator model, and varies with the condition of the second pipeline section. 压缩机0 This result is derived from computer simulation calculations, the specific calculation process of which is well known to those skilled in the art and will not be elaborated upon here. (Compare with P) 过滤器2 The actual pressure outlet value P3 of the second pipe section can be calculated. If P3 > aP 压缩机0 If P3 < aP, then the second pipe section is deemed qualified. 压缩机0 If the second pipe section is blocked, it will affect the refrigeration and require repair.

[0070] Regarding the calculation of P3, it is understandable that in the above steps, the measured P... 过滤器2 The pressure of both the first and second pipe sections is considered simultaneously, but the pressure of the second pipe section alone cannot be determined. Therefore, in this embodiment, it is necessary to calculate the actual pressure outlet value P3 of the second pipe section. To calculate P3, the air flow rate of the second pipe section is first determined, and then the pressure of the second pipe section is derived. Specifically, based on the air flow rate m of the first pipe section measured in step S1... 压缩机1 and air pressure P 压缩机1 Then the flow rate of the second pipe section is m3 = m 过滤器2 -m 压缩机1 Substituting the flow rate m3 of the second pipe section into Bernoulli's equation, setting the elevation difference to zero, and assuming the gas density to be the same, P3 can be calculated, which will not be elaborated here.

[0071] Therefore, those skilled in the art should recognize that although numerous exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications conforming to the principles of the present invention can be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Thus, the scope of the present invention should be understood and construed as covering all such other variations or modifications.

Claims

1. A device for detecting weld leaks and weld plugs in refrigerators, characterized in that, The refrigerator includes a refrigeration circuit, on which a filter and a compressor are installed. The target pipe section to be inspected is located between the filter and the compressor. The weld leak / plug detection device includes: A gas source interface is used to connect to an external gas source to obtain detection gas from the external gas source; The first detection pipeline has a first outlet end connected to the compressor; The second detection pipeline has a second air outlet end that is connected to the filter; An airflow switching valve assembly is connected to the gas source interface, the first detection pipeline, and the second detection pipeline, and is used to selectively supply the detection gas to the first detection pipeline or the second detection pipeline; A measuring component is disposed in the first detection pipeline and the second detection pipeline to obtain the gas flow rate and gas pressure at the first outlet end of the first detection pipeline and the gas flow rate and gas pressure at the second outlet end of the second detection pipeline. The processor is used to determine whether there is a weld leak or weld blockage in the target pipe section of the refrigeration circuit based on the flow rate difference of the detected gas between the first gas outlet of the first detection pipe and the second gas outlet of the second detection pipe, and / or the gas pressure value of the first detection pipe or the second detection pipe. The refrigeration circuit consists of a first pipe section and a second pipe section. The first pipe section is the pipe section between the compressor and the filter and flows through the evaporator of the refrigerator. The second pipe section is the pipe section between the compressor and the filter and flows through the condenser of the refrigerator. The second detection pipeline is configured to open when the target pipeline segment is the first pipeline segment, so that the detection gas enters the first pipeline segment and the second pipeline segment respectively from the filter, so that the detection gas flows to the compressor in the first pipeline segment, and then enters the first detection pipeline from the compressor, and the detection gas is sealed in the second pipeline segment and cannot flow out.

2. The weld leak / plug detection device according to claim 1, characterized in that, The processor is configured to determine whether the flow difference is zero when the second detection pipeline is opened, and if the flow difference is zero, determine that there is no weld leak or blockage in the first pipeline section; otherwise, continue to determine whether the air pressure value of the first detection pipeline is greater than a preset air pressure value. If the air pressure value is greater than the preset air pressure value, determine that there is no weld leak or blockage in the first pipeline section; otherwise, determine that there is a weld leak or blockage in the first pipeline section.

3. The weld leak / plug detection device according to claim 1, characterized in that, The first detection pipeline is configured to open when the target pipeline segment is the second pipeline segment, so that the detection gas enters the first pipeline segment and the second pipeline segment respectively from the compressor, and the detection gas flows to the filter in the first pipeline segment and the second pipeline segment, and then enters the second detection pipeline from the filter.

4. The weld leak / plug detection device according to claim 1, characterized in that, It also includes a main pipeline for connecting the gas source, the main pipeline connecting the first detection pipeline and the second detection pipeline.

5. The weld leak / plug detection device according to claim 4, characterized in that, The main pipeline is equipped with a gas path switching valve, which is configured to allow either the second detection pipeline or the first detection pipeline to be opened. The gas path switching valve is located at the junction of the main pipeline and the first detection pipeline and the second detection pipeline.

6. The weld leak / plug detection device according to claim 4, characterized in that, The main pipeline is equipped with a gas pressure sensor, and the output of the gas pressure sensor is connected to the processor.

7. A method for detecting weld leaks and weld plugs in refrigerators, characterized in that, The detection of weld leaks and weld plugs using the detection device as described in any one of claims 1 to 6 includes the following steps: The flow rate and pressure of the gas at the first outlet of the first detection pipeline of the weld leak and weld plug detection device are obtained, and the flow rate and pressure of the gas at the second outlet of the second detection pipeline of the weld leak and weld plug detection device are also obtained. The difference between the flow rate at the first outlet and the flow rate at the second outlet is obtained by subtracting the flow rate at the first outlet and the flow rate at the second outlet. The presence of weld leaks or blockages in the target pipe section of the refrigeration circuit is determined based on the flow rate difference of the detected gas between the first outlet end of the first detection pipe and the second outlet end of the second detection pipe, and / or the gas pressure value of the first detection pipe or the second detection pipe.

8. The method for detecting weld leaks and weld plugs according to claim 7, characterized in that, The refrigeration circuit consists of a first pipe section and a second pipe section. The first pipe section is the pipe section between the compressor and the filter and flows through the evaporator of the refrigerator. The second pipe section is the pipe section between the compressor and the filter and flows through the condenser of the refrigerator. The step of subtracting the flow rate value of the first outlet and the flow rate value of the second outlet to obtain the flow rate difference between the first outlet and the second outlet specifically includes the following steps: Obtain the first flow difference between the flow rate at the first outlet and the flow rate at the second outlet when the target pipe segment is the first pipe segment; and calculate whether there is a weld leak in the first pipe segment based on the first flow difference. Obtain the second flow difference between the flow rate at the first outlet and the flow rate at the second outlet when the target pipe segment is the second pipe segment. Based on the second flow difference and the weld leakage condition of the first pipe segment, calculate whether there is a weld leakage condition in the second pipe segment.

9. The method for detecting weld leaks and weld plugs according to claim 8, characterized in that, The step of determining whether there is a weld leak or blockage in the target pipe section of the refrigeration circuit based on the flow rate difference of the detected gas between the first outlet end of the first detection pipe and the second outlet end of the second detection pipe, and / or the gas pressure value of the first detection pipe or the second detection pipe, specifically includes the following steps: By comparing the air pressure value of the first detection pipeline with the theoretical air pressure value of the first detection pipeline, it can be determined whether there is a weld blockage problem in the first pipeline section; Based on the air pressure value of the first detection pipeline when the target pipe section is the first pipe section, and the air pressure values ​​of the first detection pipeline, the second detection pipeline, and the main pipeline when the target pipe section is the second pipe section, the actual pressure outlet value of the second pipe section is calculated. By comparing the actual pressure outlet value of the second pipe section with the theoretical air pressure value, it is determined whether there is a weld blockage problem in the second pipe section.

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