Gas circuit structure and leakage detection device

Abstract

The utility model relates to the technical field of leakage detection, and provides a gas circuit structure and a leakage detection device.The gas circuit structure comprises a first gas circuit, a second gas circuit, a differential pressure transmitter and a third gas circuit. The first gas circuit comprises a gas inlet, a first control valve and a gas outlet which are communicated in sequence, and the gas outlet is used for being communicated with a to-be-detected leakage piece. The air inlet end of the second air path communicates with the first air path at the first communicating position. The gas outlet end of the second gas circuit is used for communicating with a reference container. The second gas circuit is provided with a fourth control valve. The third gas path is provided with a first needle valve, and the cross section of the first needle valve is smaller than that of the first gas path; and when the gas path structure carries out gas inlet, the moment that the first gas path stops gas inlet is earlier than the moment that the third gas path stops gas inlet, so that the gas pressure in the gas path structure reaches a preset gas pressure value. When the gas circuit structure is used for carrying out a leakage detection test on the to-be-detected piece, the sensitivity and the test efficiency of the leakage detection test can be improved. In addition, the interior of the air channel structure can reach a preset air pressure value more accurately.

Description

Technical Field

[0001] This application relates to the field of leak detection technology, specifically to a gas path structure and a leak detection device. Background Technology

[0002] Flow meters are essential measuring instruments in industrial production and manufacturing. To ensure the airtightness of flow meters, leak tests are currently required before they leave the factory.

[0003] In existing technology, when performing leak testing on a flow meter, the inlet and outlet of the flow meter to be tested are first sealed; then, the first end of a pressure tube is inserted into the inlet or outlet of the flow meter; next, an absolute pressure transmitter and a valve are installed on the pressure tube, with the absolute pressure transmitter closer to the flow meter to be tested than the valve; then, an air filling device is connected to the second end of the pressure tube; then, a certain amount of gas is filled into the cavity of the flow meter to be tested through the pressure tube using the air filling device until the reading of the absolute pressure transmitter reaches the preset air pressure value, then the air filling is stopped and the valve is closed; then, after waiting for a period of time, the air pressure value of the absolute pressure transmitter is observed to see if it drops, thereby determining whether there is an air leak in the flow meter to be tested.

[0004] However, when using this method to test for leaks in flow meters, the testing efficiency is low and the sensitivity is poor. Utility Model Content

[0005] This application provides a gas path structure and a leak detection device. When using this gas path structure to perform leak detection tests on the component to be tested, the leak detection efficiency and test sensitivity can be improved.

[0006] To achieve the above objectives, this application adopts the following technical solution:

[0007] In a first aspect, this application provides a gas path structure, comprising: a first gas path, a second gas path, a differential pressure transmitter, and a third gas path. The first gas path includes an inlet, a first control valve, and an outlet connected sequentially, the outlet being used to communicate with a leaking component to be inspected. The inlet of the second gas path is connected to the first gas path at a first connection point. The first connection point is located between the first control valve and the outlet, the outlet of the second gas path is used to communicate with a reference container, and the second gas path is equipped with a fourth control valve and a fifth control valve (122).

[0008] The first measuring terminal of the differential pressure transmitter is connected to the second gas path at the second connection position, and the second connection position is located between the first connection position and the fourth control valve; the second measuring terminal of the differential pressure transmitter is connected to the second gas path at the third connection position, and the third connection position is located between the gas outlet of the second gas path and the fourth control valve.

[0009] The first end of the third air passage is connected to the first air passage at the fourth connecting position, and the fourth connecting position is located between the first connecting position and the first control valve; the second end of the third air passage is connected to the second air passage at the fifth connecting position, and the fifth connecting position is located between the third connecting position and the fourth control valve, and the fifth control valve is located between the fifth connecting position and the third connecting position.

[0010] The third air passage is equipped with a first needle valve, the cross-section of which is smaller than that of the first air passage; when the air passage structure is inlet, the first air passage stops inleting air earlier than the third air passage stops inleting air, so that the air pressure inside the air passage structure reaches a preset air pressure value.

[0011] As an optional implementation, the gas path structure further includes: a second needle valve, an absolute pressure transmitter, a third control valve, and a fourth gas path. The second needle valve is connected to the third gas path. The absolute pressure transmitter is connected to the third gas path and is located between the second needle valve and the fourth connection position; the third control valve is connected to the first gas path and is located between the fourth connection position and the first connection position.

[0012] The inlet of the fourth air passage is connected to the first air passage and is located between the first control valve and the third control valve. The outlet of the fourth air passage is provided with a second control valve.

[0013] As an optional implementation, the first air path is provided with a pressure regulating valve and a third needle valve, wherein the third needle valve is located between the first control valve and the pressure regulating valve.

[0014] As an optional implementation, the air inlet of the fourth air passage is located at the fourth connecting position.

[0015] As an optional implementation, the first control valve, the second control valve, the third control valve, the fourth control valve and / or the fifth control valve are electromagnetic control valves.

[0016] As an optional implementation, the gas path structure further includes a control component, which is electrically connected to the first control valve, the second control valve, the third control valve, the fourth control valve and / or the fifth control valve.

[0017] As an optional implementation, the control component is electrically connected to the differential pressure transmitter and the absolute pressure transmitter, and is used to automatically control the opening or closing of the differential pressure transmitter and the absolute pressure transmitter.

[0018] As an optional implementation, the range of the differential pressure transmitter is 1‰ of the range of the absolute pressure transmitter.

[0019] Secondly, this application provides a leak detection device, which includes the gas path structure and reference container described in any of the first aspects above, wherein the reference container is detachably connected to the gas outlet of the second gas path.

[0020] As an optional implementation, there are multiple reference containers, and the volumes of any two reference containers differ. The outlet of the second gas path is detachably connected to one of the multiple reference containers.

[0021] Compared with the prior art, the beneficial effects of this application are at least as follows:

[0022] The gas path structure includes a first gas path, a second gas path, a differential pressure transmitter, a first control valve, a fourth control valve, and a fifth control valve. The leaking component to be tested is connected to the outlet of the first gas path, and the reference container is connected to the outlet of the second gas path.

[0023] When using this air path structure to perform a leak test on the component under test, gas is first introduced into the air path structure through the air inlet of the first air path. At this time, the air pressure values ​​inside the component under test and the reference container are the same. Then, after closing the first control valve and the fourth control valve, the component under test is isolated from the reference container. At this time, the first measuring terminal of the differential pressure transmitter can measure the first air pressure value inside the component under test, and the second measuring terminal of the differential pressure transmitter can measure the second air pressure value inside the reference container, thus obtaining a pressure difference value. Then, after waiting for a short time, if the pressure difference value remains unchanged, it can be proved that the air tightness of the component under test is qualified; if the pressure difference value changes, it can be proved that the air tightness of the component under test is unqualified.

[0024] Because the range of the differential pressure transmitter is smaller than that of the absolute pressure transmitter, even if the cavity volume of the component under test is large and the leak point is small, as long as the component under test shows a leak, the air pressure difference value displayed by the differential pressure transmitter will change significantly. Therefore, it is easy to determine whether the air tightness of the component under test is good, thus making the sensitivity higher when performing leak testing on the component under test.

[0025] Next, since the differential pressure transmitter will show a significant change in pressure difference as soon as a leak is detected in the component under test, the leak test results can be obtained in a short time after gas is introduced into the flowmeter chamber. This reduces the time required to test each component, thus improving the efficiency of leak testing.

[0026] Next, to accurately inflate the gas path structure and achieve a preset internal pressure, the gas path structure includes a third gas path. The first end of the third gas path connects to the first gas path at a fourth connection position, located between the first connection position and the first control valve. The second end of the third gas path connects to the second gas path at a fifth connection position, located between the third connection position and the fourth control valve. The third gas path is equipped with a first needle valve, the cross-section of which is smaller than that of the first gas path. When the gas path structure is inlet, the first gas path stops inletting air earlier than the third gas path, ensuring that the internal pressure of the gas path structure reaches the preset pressure value.

[0027] When inflating this air passage structure, inflation can begin primarily through the first air passage. Then, when the actual air pressure inside the structure is close to the preset pressure, inflation through the first air passage is stopped. Inflation then continues solely through the third air passage until the actual air pressure accurately reaches the preset pressure. Inflating primarily through the first air passage allows the actual pressure to approach the preset pressure relatively quickly. Continuing inflation through the third air passage, with its smaller cross-section (first needle valve), allows for slower inflation, resulting in a more precise attainment of the preset pressure compared to inflating solely through the first air passage. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of a gas path structure provided in an embodiment of this application;

[0030] Figure 2 This is a schematic diagram of a leak detection device provided in an embodiment of this application.

[0031] Explanation of reference numerals in the attached figures:

[0032] 100 - Gas path structure, 110 - First gas path, 111 - Air inlet, 112 - Pressure regulating valve, 113 - First control valve, 114 - Air outlet, 115 - Third control valve, 116 - Third needle valve, 120 - Second gas path, 121 - Fourth control valve, 122 - Fifth control valve, 130 - Differential pressure transmitter, 140 - Third gas path, 141 - First needle valve, 142 - Second needle valve, 150 - Absolute pressure transmitter, 160 - Fourth gas path, 161 - Second control valve, A1 - First connection position, A2 - Second connection position, A3 - Third connection position, A4 - Fourth connection position, A5 - Fifth connection position, 200 - Reference container, 1000 - Leak detection device

[0033] B - Missing items to be inspected. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0035] In the prior art, when performing a leak test on a flow meter, the flow meter to be tested is first sealed; then, an inflation device is used to fill the cavity of the flow meter to be tested with a certain amount of gas through a pressure pipe until the reading of the absolute pressure transmitter reaches the preset gas pressure value, and then the inflation is stopped; then, after waiting for a period of time, the gas pressure value of the absolute pressure transmitter is observed to see if it drops, so as to determine whether there is a leak in the flow meter to be tested.

[0036] However, because this absolute pressure transmitter needs to perform leak tests on various flow meters, and different flow meters require different air pressure values ​​for testing, with a wide range of these different air pressure values, this absolute pressure transmitter has a large range to meet this requirement.

[0037] Because this absolute pressure transmitter has a large measuring range, the scale division on its dial is relatively large. When the flow meter under test has a large cavity volume and a small leak point, the gas filling the cavity decreases very slowly. Therefore, the pressure decreases very slowly in the cavity and pressure tube, insufficient to cause a significant change in the absolute pressure transmitter's dial reading. Consequently, it is difficult to determine the airtightness of the flow meter under test based on the change in the absolute pressure transmitter's reading. Thus, this method has poor sensitivity when used for leak testing of flow meters.

[0038] Furthermore, when the flowmeter under test has a large cavity volume and a small leak point, a considerable amount of time is required after filling the flowmeter cavity with gas in order to achieve a significant change in the absolute pressure transmitter's dial reading. This results in a long testing time for each flowmeter, making this method inefficient for leak testing.

[0039] Based on the above-mentioned technical problems, the gas path structure provided by this utility model includes a first gas path, a second gas path, a differential pressure transmitter, a first control valve, and a fourth control valve. The leaking part to be tested is connected to the outlet of the first gas path, and the reference container is connected to the outlet of the second gas path.

[0040] When this air path structure is used to perform a leak test on the component under test, gas is first introduced into the air path structure through the air inlet of the first air path. At this time, the air pressure values ​​inside the component under test and the reference container are the same. Then, after closing the first control valve and the fourth control valve, the component under test is isolated from the reference container by the fourth control valve. At this time, the first measuring terminal of the differential pressure transmitter can measure the first air pressure value inside the component under test, and the second measuring terminal of the differential pressure transmitter can measure the second air pressure value inside the reference container, thus obtaining a pressure difference value. Then, after waiting for a short time, if the pressure difference value remains unchanged, it can be proved that the air tightness of the component under test is qualified; if the pressure difference value changes, it can be proved that the air tightness of the component under test is unqualified.

[0041] Because the range of the differential pressure transmitter is smaller than that of the absolute pressure transmitter, even if the cavity volume of the component under test is large and the leak point is small, as long as the component under test shows a leak, the air pressure difference value displayed by the differential pressure transmitter will change significantly. Therefore, it is easy to determine whether the air tightness of the component under test is good, thus making the sensitivity higher when performing leak testing on the component under test.

[0042] Next, since the differential pressure transmitter will show a significant change in pressure difference as soon as a leak is detected in the component under test, the leak test results can be obtained in a short time after gas is introduced into the flowmeter chamber. This reduces the time required to test each component, thus improving the efficiency of leak testing.

[0043] The contents of this application will now be described in detail with reference to the accompanying drawings, so that those skilled in the art can have a clearer and more detailed understanding of the contents of this application.

[0044] The following provides a detailed description of the specific structure of the above-mentioned gas path structure and various possible implementation methods.

[0045] Figure 1 This is a schematic diagram of a gas path structure 100 provided in an embodiment of this application.

[0046] See Figure 1 The gas path structure 100 includes: a first gas path 110, a second gas path 120, a differential pressure transmitter 130, and a third gas path 140. The first gas path 110 includes an inlet 111, a pressure regulating valve 112, a first control valve 113, and an outlet 114 connected in sequence. The outlet 114 is used to connect with the leaking component B to be inspected. The inlet of the second gas path 120 is connected to the first gas path 110 at a first connection position A1. The first connection position A1 is located between the first control valve 113 and the outlet 114. The outlet of the second gas path 120 is used to connect with a reference container 200. The second gas path 120 is equipped with a fourth control valve 121 and a fifth control valve 122.

[0047] The first measuring terminal of the differential pressure transmitter 130 is connected to the second gas path 120 at the second connecting position A2, which is located between the first connecting position A1 and the fourth control valve 121; the second measuring terminal of the differential pressure transmitter 130 is connected to the second gas path 120 at the third connecting position A3, which is located between the gas outlet of the second gas path 120 and the fourth control valve 121.

[0048] The first end of the third air passage 140 is connected to the first air passage 110 at the fourth connecting position A4, which is located between the first connecting position A1 and the first control valve 113; the second end of the third air passage 140 is connected to the second air passage 120 at the fifth connecting position A5, which is located between the third connecting position A3 and the fourth control valve 121, and the fifth control valve 122 is located between the fifth connecting position A5 and the third connecting position A3.

[0049] The third air passage 140 is provided with a first needle valve 141, the cross-section of the first needle valve 141 is smaller than the cross-section of the first air passage 110; when the air passage structure 100 is inlet, the first air passage 110 stops inleting air earlier than the third air passage 140 stops inleting air, so that the air pressure inside the air passage structure 100 reaches the preset air pressure value.

[0050] In this embodiment, the gas path structure 100 includes a first gas path 110, a second gas path 120, a differential pressure transmitter 130, a first control valve 113, a fourth control valve 121, and a fifth control valve 122. The leaking component B to be tested is connected to the outlet 114 of the first gas path 110, and the reference container 200 is connected to the outlet of the second gas path 120.

[0051] When the gas path structure 100 is used to perform a leak test on the component B to be tested, gas is first introduced into the gas path structure 100 through the air inlet 111 of the first gas path 110. At this time, the gas pressure values ​​inside the component B to be tested and the reference container 200 are the same. Then, after closing the first control valve 113 and the fourth control valve 121, the component B to be tested is isolated from the reference container 200. At this time, the first measuring end of the differential pressure transmitter 130 can measure the first gas pressure value inside the component to be tested, and the second measuring end of the differential pressure transmitter 130 can measure the second gas pressure value inside the reference container 200, thereby obtaining a pressure difference value. Then, after waiting for a short time, if the pressure difference value remains unchanged, it can be proved that the airtightness of the component B to be tested is qualified; if the pressure difference value changes, it can be proved that the airtightness of the component B to be tested is unqualified.

[0052] Since the range of the differential pressure transmitter 130 is smaller than that of the absolute pressure transmitter 150, even if the cavity volume of the component B to be tested is large and the leak point is small, as long as the component B to be tested has a leak, the air pressure difference value displayed by the differential pressure transmitter 130 will change significantly. Therefore, it is easy to determine whether the air tightness of the component B to be tested is good, thus making the sensitivity higher when performing leak testing on the component B to be tested.

[0053] Next, since the differential pressure transmitter 130 will show a significant change in pressure difference as soon as the leaking component B is detected, the leak test results can be obtained after only a short waiting time after the flowmeter cavity is filled with gas. This reduces the time required to test each leaking component B, thus improving the efficiency of the leak test.

[0054] Next, in order to accurately inflate the air passage structure 100 to achieve a preset air pressure value, the air passage structure 100 includes a third air passage 140. The first end of the third air passage 140 is connected to the first air passage 110 at a fourth connection position A4, which is located between the first connection position A1 and the first control valve 113. The second end of the third air passage 140 is connected to the second air passage 120 at a fifth connection position A5, which is located between the third connection position A3 and the fourth control valve 121. The third air passage 140 is equipped with a first needle valve 141, the cross-section of which is smaller than that of the first air passage 110. When the air passage structure 100 is inletting air, the first air passage 110 stops inletting air earlier than the third air passage 140, so that the air pressure inside the air passage structure 100 reaches the preset air pressure value.

[0055] When inflating the air passage structure 100, it can be primarily inflated through the first air passage 110. Then, when the actual air pressure inside the air passage structure 100 is close to the preset air pressure value, inflation through the first air passage 110 is stopped. Inflation then continues only through the third air passage 140 until the actual air pressure inside the air passage structure 100 accurately reaches the preset air pressure value. In the inflation process, primarily inflating through the first air passage 110 allows the actual air pressure value to approach the preset air pressure value relatively quickly, in a shorter time. Continuing inflation through the third air passage 140, because the third air passage 140 is equipped with a first needle valve 141, whose cross-section is smaller than that of the first air passage 110, allows for slower inflation of the air passage structure 100. Compared to the scheme of inflating only through the first air passage 110, this allows the actual air pressure value to reach the preset air pressure value more accurately.

[0056] It should be noted that the air inlet 111 is used to connect to an inflation device, which is used to fill the air passage structure 100 with gas through the air inlet 111. The inflation device can be an air pump or an air cylinder, or other devices with inflation function. This application embodiment does not limit this.

[0057] It should also be noted that the pressure regulating valve 112 is used to regulate the intake flow of the first air passage 110.

[0058] It should also be noted that the aforementioned leak-testing component B can be a flow meter or a sealed container, or other devices that require leak testing. This application embodiment does not limit this.

[0059] As an optional implementation, in some embodiments, see [link to relevant documentation]. Figure 1 The pneumatic circuit structure 100 further includes: a second needle valve 142, an absolute pressure transmitter 150, a third control valve 115, and a fourth pneumatic circuit 160. The second needle valve 142 is connected to the third pneumatic circuit 140. The absolute pressure transmitter 150 is connected to the third pneumatic circuit 140 and is located between the second needle valve 142 and the fourth connection position A4; the third control valve 115 is connected to the first pneumatic circuit 110 and is located between the fourth connection position A4 and the first connection position A1.

[0060] The inlet of the fourth air passage 160 is connected to the first air passage 110 and is located between the first control valve 113 and the third control valve 115. The outlet of the fourth air passage 160 is provided with a second control valve 161.

[0061] In this embodiment, when determining the airtightness of the leak test component B by measuring the air pressure difference of the differential pressure transmitter 130, it is necessary to assume that the fourth control valve 121 and the fifth control valve 122 are airtight as described above. Specifically, to ensure the accuracy of the leak test results for the leak test component B, while observing the change in the air pressure difference of the differential pressure transmitter 130, it is necessary to ensure that the fourth control valve 121 and the fifth control valve 122 are airtight.

[0062] Because the absolute pressure transmitter 150 is connected to the third gas path 140, when performing a leak test on the component B to be tested, the gas path structure 100 is first inflated so that the reading of the absolute pressure transmitter 150 reaches the first preset gas pressure value; then the first control valve 113, the third control valve 115, the fourth control valve 121, and the fifth control valve 122 are closed, and the second needle valve 142 and the second control valve 161 are opened and the first gas is released through the second control valve 161. When the reading of the absolute pressure transmitter 150 reaches the second preset gas pressure value, the second control valve 161 is closed. At this time, the first control valve 142 is closed. 13. The second control valve 161, the third control valve 115, the fourth control valve 121, the fifth control valve 122, the first air passage 110, and the third air passage 140 form a first sealed space. Then observe the reading of the insulation transmitter. If the reading of the insulation transmitter remains at the second preset air pressure value, it can be proved that the air tightness of the fourth control valve 121 and the fifth control valve 122 is good. If the air pressure difference of the differential pressure transmitter 130 does not change, it can be proved that the air tightness of the leaking component B under test is good.

[0063] The second needle valve 142 can replace the first needle valve 141. When the first needle valve 141 malfunctions and cannot reduce the gas flow, the second needle valve 142 can be used to replace the first needle valve 141, thereby improving the accuracy of leak detection.

[0064] As an optional implementation, in some embodiments, see [link to relevant documentation]. Figure 1 The first air passage 110 is equipped with a pressure regulating valve 112 and a third needle valve 116, with the third needle valve 116 located between the first control valve 113 and the pressure regulating valve 112.

[0065] In this way, when it is necessary to control the intake air flow, the opening of the third needle valve 116 can be adjusted so that the gas passes through the third needle valve 116 before passing through the first needle valve 141, thereby reducing the gas flow and thus strengthening the effect of the first needle valve 141.

[0066] In addition, the third needle valve 116 can replace the first needle valve 141. When the first needle valve 141 malfunctions and cannot reduce the gas flow, the third needle valve 116 can be used to replace the first needle valve 141, which further improves the accuracy of leak detection.

[0067] It should be noted that the first needle valve 141, the second needle valve 142 and the third needle valve 116 mentioned above can be manual needle valves or automatic needle valves, and this application embodiment does not limit them.

[0068] As an optional implementation, in some embodiments, see [link to relevant documentation]. Figure 1 The air intake end of the fourth air passage 160 is located at the fourth connecting position A4.

[0069] This allows for the installation of a four-way connector at the fourth connection position A4. The first and second interfaces of this four-way connector are connected to the first air passage 110, the third interface is connected to the third air passage 140, and the fourth interface is connected to the fourth air passage 160. This makes the air passage structure 100 simpler and more organized, facilitating future maintenance.

[0070] As an optional implementation, in some embodiments, see [link to relevant documentation]. Figure 1 The first control valve 113, the second control valve 161, the third control valve 115, the fourth control valve 121 and / or the fifth control valve 122 are electromagnetic control valves.

[0071] Because electromagnetic control valves possess high reliability and stability, they can operate in relatively harsh environments, thus expanding the applicability of the pneumatic circuit structure 100. Furthermore, the fast response speed of electromagnetic control valves enables precise control, facilitating the control of the pneumatic circuit structure 100 based on external conditions. This, in turn, facilitates the automatic control of the pneumatic circuit structure 100.

[0072] As an optional implementation, in some embodiments, see [link to relevant documentation]. Figure 1 The gas path structure 100 also includes a control component, which is electrically connected to the first control valve 113 and is used to automatically control the first control valve 113. Specifically, the control component can control the on / off state and the opening degree of the first control valve 113, thus facilitating the automatic control of the gas path structure 100.

[0073] Alternatively, the control component may be electrically connected to the second control valve 161 for automatic control of the second control valve 161. Alternatively, the control component may be electrically connected to the third control valve 115 for automatic control of the third control valve 115. Alternatively, the control component may be electrically connected to the fourth control valve 121 for automatic control of the fourth control valve 121. Alternatively, the control component may be electrically connected to the fifth control valve 122 for automatic control of the fifth control valve 122. The technical effect corresponding to this feature is the same as the above-described technical effects, and therefore will not be repeated here.

[0074] As an optional implementation, in some embodiments, see [link to relevant documentation]. Figure 1The control component is electrically connected to the differential pressure transmitter 130 and the absolute pressure transmitter 150, and is used to automatically control the opening or closing of the differential pressure transmitter 130 and the absolute pressure transmitter 150. Specifically, the opening or closing of the differential pressure transmitter 130 and the absolute pressure transmitter 150 can be controlled by the control component, which is beneficial to the automatic control of the gas path structure 100.

[0075] As an optional implementation, in some embodiments, see [link to relevant documentation]. Figure 1 The range of differential pressure transmitter 130 is 1‰ of the range of absolute pressure transmitter 150.

[0076] By reducing the range of the differential pressure transmitter 130, the scale division of the transmitter 130 dial can be reduced. This makes changes in the pressure difference easier to observe, thereby improving the accuracy of leak detection.

[0077] Through testing, it has been verified that when the range of the differential pressure transmitter 130 is 1‰ of the range of the absolute pressure transmitter 150, it is beneficial for technicians to read the pressure difference while ensuring test accuracy, thus improving test efficiency.

[0078] See Figure 2 This application embodiment also provides a leak detection device 1000, which includes any of the above-described air passage structures 100 and a reference container 200, wherein the reference container 200 is detachably connected to the air outlet of the second air passage 120.

[0079] When using the leak detection device 1000 to perform leak tests on different types of leak-testing components B, different reference containers 200 are required. The reference container 200 is detachably connected to the outlet of the second air passage 120, making it easy to replace different reference containers 200. This improves the efficiency of testing when using the leak detection device 1000 to test various different leak-testing components B.

[0080] As an optional implementation, in some embodiments, see [link to relevant documentation]. Figure 2 There are multiple reference containers 200, and the volumes of any two reference containers 200 are different. The outlet of the second gas path 120 is detachably connected to one of the multiple reference containers 200.

[0081] In this way, each reference container 200 has a different volume, and reference containers 200 with different volumes can be used to perform leak testing on leak-testing components B with different volumes, thereby expanding the applicability of the leak testing device 1000.

[0082] This application embodiment also provides a leak detection method, which is applied to the aforementioned leak detection device 1000, and the leak detection method includes:

[0083] Step 1: Connect the leaking component B to the outlet 114 of the first air passage 110.

[0084] Step 2: Control the first needle valve 141, the second needle valve 142, the third needle valve 116, the first control valve 113, the third control valve 115, the fourth control valve 121, and the fifth control valve 122 to open and close the second control valve 161.

[0085] Step 3: Control the filling of the gas path structure 100 with test gas through the air inlet 111 of the first gas path 110 until the actual gas pressure value displayed by the absolute pressure transmitter 150 reaches 90% of the first preset gas pressure value, and then stop filling the gas.

[0086] This step allows the actual air pressure value to approach the preset air pressure value relatively quickly, and the process is relatively short. This short process improves the efficiency of leak testing.

[0087] Step 4: Control the closing of the third control valve 115, and continue to charge the detection gas into the gas path structure 100 through the air inlet 111 of the first gas path 110 until the actual gas pressure value displayed by the absolute pressure transmitter 150 reaches 100% of the first preset gas pressure value, then stop charging and close the first control valve 113.

[0088] Since the cross-section of the first needle valve 141 is smaller than the cross-section of the first air passage 110, this step allows for slow inflation of the air passage structure 100, thereby enabling the actual air pressure value to more accurately reach the first preset air pressure value. This, in turn, makes the leak test results more accurate.

[0089] Step 5: Control and observe the reading of the absolute pressure transmitter 150 to ensure that the reading of the absolute pressure transmitter 150 remains stable.

[0090] When the reading of the absolute pressure transmitter 150 remains stable, it can be proven that the internal airtightness of the gas path structure 100 is good. This condition is a prerequisite for leak detection.

[0091] Step 6: Close the first control valve 113, the third control valve 115, the fourth control valve 121 and the fifth control valve 122 and open the second control valve 161. After the actual air pressure value displayed by the absolute pressure transmitter 150 reaches the second preset air pressure value, close the second control valve 161.

[0092] Specifically, the first preset air pressure value is greater than the applicable maximum air pressure value of the leaking component B to be tested. The first preset air pressure value is set according to the actual leaking component B to be tested, and is generally 1.1 times the applicable maximum air pressure value of the leaking component B to be tested.

[0093] The second preset air pressure value is 10%-90% of the first preset air pressure value, and the second preset air pressure value is generally set to 50% of the first preset air pressure value.

[0094] Step 7: Control and observe the readings of the absolute pressure transmitter 150 and the differential pressure transmitter 130. If the readings of the absolute pressure transmitter 150 and the differential pressure transmitter 130 remain stable, it proves that the airtightness of the leaking component B under test is good; otherwise, it proves that the airtightness of the leaking component B under test is unqualified.

[0095] The stable and unchanged reading of the absolute pressure transmitter 150 proves that the fourth control valve 121 and the fifth control valve 122 are airtight. Based on this, the stable and unchanged reading of the differential pressure transmitter 130 proves that there is no air leakage in the component B under test, thus proving that the component B under test is airtight.

[0096] Step 8: Control the opening of the first control valve 113, the second control valve 161, the third control valve 115, the fourth control valve 121 and the fifth control valve 122 to release the gas in the leak-to-be-tested component B and the reference container 200, and disassemble the leak-to-be-tested component B.

[0097] After this step is completed, the above steps can be repeated to continue the leak test on the next component B to be tested for leaks.

[0098] When the above-mentioned leak detection method is used to test the leak of component B, since the range of the differential pressure transmitter 130 is smaller than that of the absolute pressure transmitter 150, even if the cavity volume of component B is large and the leak point is small, as long as the component B shows a leak, the air pressure difference value displayed by the differential pressure transmitter 130 will change significantly. Therefore, it is easy to determine whether the air tightness of component B is good, thus making the leak detection test of component B more sensitive.

[0099] Next, since the differential pressure transmitter 130 will show a significant change in pressure difference as soon as the leaking component B is detected, the leak test results can be obtained after only a short waiting time after the flowmeter cavity is filled with gas. This reduces the time required to test each leaking component B, thus improving the efficiency of the leak test.

[0100] Next, since the air passage structure 100 includes a third air passage 140, the first end of the third air passage 140 is connected to the first air passage 110 at the fourth connection position A4, which is located between the first connection position A1 and the first control valve 113; the second end of the third air passage 140 is connected to the second air passage 120 at the fifth connection position A5, which is located between the third connection position A3 and the fourth control valve 121. The third air passage 140 is provided with a first needle valve 141, the cross-section of which is smaller than that of the first air passage 110; when the air passage structure 100 is intake, the first air passage 110 stops intake earlier than the third air passage 140 stops intake, so that the air pressure inside the air passage structure 100 reaches a preset air pressure value.

[0101] In this way, during the inflation process, inflation is primarily conducted through the first air passage 110, which allows the actual air pressure value to approach the preset air pressure value relatively quickly, in a shorter time. Inflation then continues through the third air passage 140. Because the third air passage 140 is equipped with a first needle valve 141, the cross-section of which is smaller than that of the first air passage 110. This allows for slower inflation of the air passage structure 100, enabling the actual air pressure value to reach the preset air pressure value more accurately compared to inflation only through the first air passage 110.

[0102] It should be noted that the terms "one embodiment," "embodiment," "exemplary embodiment," "some embodiments," etc., mentioned in the specification indicate that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Moreover, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments, whether explicitly described or not, is within the knowledge scope of those skilled in the art.

[0103] Generally speaking, terms should be understood at least in part by their use in context. For example, at least in part by context, the term "one or more" as used in the text can be used to describe any feature, structure, or characteristic of the singular meaning, or a combination of features, structures, or characteristics of the plural meaning. Similarly, at least in part by context, terms such as "a" or "the" can also be understood to convey either singular or plural usage.

[0104] It should be readily understood that the terms “on,” “above,” and “on top of” in this application should be interpreted in the broadest possible sense, such that “on” means not only “directly on something,” but also “on something” with an intermediate feature or layer therebetween, and that “above” or “on top of” means not only “above something” or “on top of something,” but also “on something” or “on top of something” without an intermediate feature or layer therebetween, i.e., directly on something.

[0105] Furthermore, for ease of explanation, spatially relative terms such as "below," "below," "under," "above," and "above" may be used to describe the relationship of one element or feature relative to other elements or features as shown in the figures. Spatially relative terms are intended to encompass different orientations of the device in use or operation other than those shown in the figures. The device may have other orientations rotated 90° or be in other orientations, and the spatially relative descriptive terms used herein may be interpreted accordingly.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A gas path structure (100), characterized in that, include: The first air passage (110) includes an air inlet (111), a first control valve (113), and an air outlet (114) connected in sequence. The air outlet (114) is used to connect with the leaking component (B) to be inspected. The second air passage (120) has an inlet end connected to the first air passage (110) at a first connection position (A1); the first connection position (A1) is located between the first control valve (113) and the outlet (114); the outlet end of the second air passage (120) is used to connect to the reference container (200); the second air passage (120) is provided with a fourth control valve (121) and a fifth control valve (122); A differential pressure transmitter (130) has its first measuring terminal connected to the second gas path (120) at a second connecting position (A2), the second connecting position (A2) being located between the first connecting position (A1) and the fourth control valve (121); the second measuring terminal of the differential pressure transmitter (130) is connected to the second gas path (120) at a third connecting position (A3), the third connecting position (A3) being located between the gas outlet of the second gas path (120) and the fourth control valve (121); A third gas path (140) has its first end connected to the first gas path (110) at a fourth connection position (A4), which is located between the first connection position (A1) and the first control valve (113); the second end of the third gas path (140) is connected to the second gas path (120) at a fifth connection position (A5), which is located between the third connection position (A3) and the fourth control valve (121), and the fifth control valve (122) is located between the fifth connection position (A5) and the third connection position (A3); The third air passage (140) is provided with a first needle valve (141), the cross-section of the first needle valve (141) is smaller than the cross-section of the first air passage (110); when the air passage structure (100) is inlet, the first air passage (110) stops inleting air earlier than the third air passage (140) stops inleting air, so that the air pressure inside the air passage structure (100) reaches a preset air pressure value.

2. The gas path structure (100) according to claim 1, characterized in that, The gas path structure (100) also includes: The second needle valve (142) is connected to the third air passage (140); Absolute pressure transmitter (150), the absolute pressure transmitter (150) is connected to the third gas passage (140), the absolute pressure transmitter (150) is located between the second needle valve (142) and the fourth connection position (A4); The third control valve (115) is connected to the first gas passage (110) and is located between the fourth connection position (A4) and the first connection position (A1). The fourth air passage (160) has an air inlet end that is connected to the first air passage (110) and located between the first control valve (113) and the third control valve (115). The air outlet end of the fourth air passage (160) is provided with a second control valve (161).

3. The gas path structure (100) according to claim 2, characterized in that, The first air passage (110) is provided with a pressure regulating valve (112) and a third needle valve (116), the third needle valve (116) being located between the first control valve (113) and the pressure regulating valve (112).

4. The gas path structure (100) according to claim 2, characterized in that, The air inlet of the fourth air passage (160) is located at the fourth connecting position (A4).

5. The gas path structure (100) according to claim 2, characterized in that, The first control valve (113), the second control valve (161), the third control valve (115), the fourth control valve (121) and / or the fifth control valve (122) are electromagnetic control valves.

6. The gas passage structure (100) according to claim 2, characterized in that, The gas path structure (100) also includes a control component, which is electrically connected to the first control valve (113), the second control valve (161), the third control valve (115), the fourth control valve (121) and / or the fifth control valve (122).

7. The gas path structure (100) according to claim 6, characterized in that, The control component is electrically connected to the differential pressure transmitter (130) and the absolute pressure transmitter (150) and is used to automatically control the opening or closing of the differential pressure transmitter (130) and the absolute pressure transmitter (150).

8. The gas passage structure (100) according to claim 2, characterized in that, The range of the differential pressure transmitter (130) is 1‰ of the range of the absolute pressure transmitter (150).

9. A leak detection device (1000), characterized in that, Includes the gas passage structure (100) and reference container (200) as described in any one of claims 1-8, wherein the reference container (200) is detachably connected to the outlet end of the second gas passage (120).

10. The leak detection device (1000) according to claim 9, characterized in that, There are multiple reference containers (200), and the volumes of any two reference containers (200) are different. The outlet of the second air passage (120) is detachably connected to one of the multiple reference containers (200).

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