Leakage rate testing device of battery top cover sealing ring

Abstract

A battery top cover sealing ring leakage rate testing device disclosed by the present invention comprises an upper clamp, a sealing cover, a lower clamp, a gas source and a calculation module or a helium mass spectrometer, the sealing cover is detachably connected to the lower clamp in a sealing manner, the top of the sealing cover is provided with a clamp connection port, and the upper clamp is slidably arranged in the clamp connection port in a penetrating manner and keeps sliding sealing with the sealing cover. The lower clamp is provided with a supporting face used for supporting the sealing ring, the upper clamp is provided with a pressing head facing the supporting face, the sealing cover is provided with an air inlet communicated with a gap between the upper clamp and the lower clamp, a cavity is formed in the lower clamp and connected with a first air channel and a second air channel, and an opening of the first air channel is formed in the supporting face. The second air channel forms an air outlet in the lower clamp, the air inlet is connected with an air source, the air outlet is connected with a helium mass spectrometer, and the calculation module or the helium mass spectrometer is used for calculating the leakage rate. The device is suitable for testing various sealing rings with different sizes, and is high in efficiency and accuracy and good in repeatability.

Description

Technical Field

[0001] The present invention relates to a leakage rate testing device for a sealing ring, belonging to the technical field of sealing performance testing of structural components. Background Art

[0002] The battery sealing ring is a key component used in battery assemblies, and its sealing performance directly affects the performance and safety of the battery. In order to ensure that the sealing ring product meets the standards and specifications, it is necessary to test its leakage rate.

[0003] Existing sealing ring testing devices have problems such as complex operation and inability to accurately measure the leakage rate. For example, in the sealing ring airtightness test device with the publication number CN114199467A, the sealing ring is used as the seal of the airtight test chamber, and the leakage is judged by observing whether there are bubbles when the airtight test chamber is placed in a water tank. Its operation process is complex, and it is necessary to prepare an airtight test chamber adapted to the size of the sealing ring, which will greatly increase the test cost for testing various different specifications of sealing rings. Summary of the Invention

[0004] Aiming at the above-mentioned defects of the existing technology, the task of the present invention is to provide a leakage rate testing device for a battery top cover sealing ring, which is applicable to the testing of various different sizes of sealing rings, improves the testing efficiency, and ensures the accuracy and repeatability of the testing.

[0005] The technical solution of the present invention is as follows: A leakage rate testing device for a battery top cover sealing ring, comprising an upper fixture, a sealing cover, a lower fixture, a gas source, and a calculation module. The sealing cover is detachably connected to the lower fixture, and a seal is provided between the sealing cover and the lower fixture. A fixture connection port is provided at the top of the sealing cover. The upper fixture slidably passes through the fixture connection port and maintains a sliding seal with the sealing cover. When the upper fixture slides, it approaches or moves away from the lower fixture. The lower fixture is provided with a support surface for supporting the sealing ring. One end of the upper fixture facing the support surface of the lower fixture is provided with a pressing head. The sealing cover is provided with an air inlet communicating with the gap between the upper fixture and the lower fixture. A cavity is provided in the lower fixture, and the cavity is connected with a first air duct and a second air duct. The opening of the first air duct is formed on the support surface, and the second air duct forms an air outlet on the lower fixture. The air inlet is connected to the gas source through a first pipeline. The first pipeline is provided with a temperature sensor and a first air pressure sensor. The air outlet is provided with a second air pressure sensor. The calculation module is electrically connected to the temperature sensor, the first air pressure sensor, and the second air pressure sensor and is used for calculating the leakage rate.

[0006] Another technical solution of the present invention is: a leakage rate testing device for a battery top cover sealing ring, comprising an upper fixture, a sealing cover, a lower fixture, a helium source and a helium mass spectrometer, wherein the sealing cover is detachably connected to the lower fixture, a seal is set between the sealing cover and the lower fixture, a fixture connection port is provided on the top of the sealing cover, the upper fixture is slidably inserted into the fixture connection port and maintains a sliding seal with the sealing cover, the upper fixture approaches or moves away from the lower fixture when sliding, the lower fixture is provided with a supporting surface for supporting the sealing ring, the upper fixture is provided with a pressure head at one end of the supporting surface facing the lower fixture, the sealing cover is provided with an air inlet connecting the gap between the upper fixture and the lower fixture, a cavity is provided in the lower fixture, the cavity is connected to a first air channel and a second air channel, the opening of the first air channel is formed on the supporting surface, the second air channel forms an air outlet on the lower fixture, the air inlet is connected to the helium source through a first pipeline, and the air outlet is connected to the helium mass spectrometer through a second pipeline.

[0007] Furthermore, the pressing head and the upper clamp are detachably connected.

[0008] Furthermore, the surface roughness of the side of the indenter facing the supporting surface and the supporting surface is Ra≤0.4.

[0009] Furthermore, it includes an environmental box, which is provided with a heating and cooling device, a part of the upper clamp, the sealing cover and a part of the lower clamp are arranged in the environmental box, and an end of the upper clamp facing away from the lower clamp and an end of the lower clamp facing away from the upper clamp are arranged outside the environmental box.

[0010] Furthermore, the ambient temperature in the environmental box is -40°C to 150°C.

[0011] Compared with the prior art, the advantages of the technical solution of the present invention are:

[0012] A sliding upper clamp and a lower clamp are used in combination, and an external pressure device (such as a hydraulic universal testing machine) can be used to apply a mutual supporting force to the upper clamp and the lower clamp, thereby controlling the sealing stress of the sealing ring set between the pressure head and the supporting surface of the lower clamp to perform a leakage rate test. Since the pressure head and the lower clamp only need to be able to closely contact the sealing ring, the contact surface and the supporting surface of the pressure head and the sealing ring only need to be set as a plane. A pressure head of one size can be suitable for sealing rings of multiple sizes, as long as the outer diameter of the sealing ring is not larger than the end face size of the pressure head. Therefore, the convenience of stress application and the strong versatility of size make the device adaptable to leakage rate tests of sealing rings of various sizes.

[0013] Since an external pressure - applying device is used to apply sealing stress to the sealing ring to be tested, it is very easy to control the magnitude of the sealing stress. Compared with the prior - art method of applying sealing stress by tightening and installing multiple bolts, the present invention has good repeatability, and only needs to install a sealing cover to ensure reliable sealing with the lower fixture, without the need to accurately align the sealing ring to be tested. Therefore, the test operation efficiency is also greatly improved.

[0014] The measurement of the leakage rate is carried out by a calculation module or a helium mass spectrometer. Combining with the cooperation structure of the upper fixture and the lower fixture, it is easier to obtain an accurate test structure. Brief Description of the Drawings

[0015] Figure 1 It is a schematic structural diagram of a leakage - rate test device for a battery top - cover sealing ring according to an embodiment of the present invention. Detailed Embodiments

[0016] The present invention will be further described below in conjunction with embodiments, but it is not intended to limit the present invention.

[0017] Please refer to Figure 1 As shown, the leakage - rate test device for a battery top - cover sealing ring according to an embodiment of the present invention includes an upper fixture 1, a sealing cover 3, a lower fixture 12, a gas source 14, and a calculation module 17. The calculation module 17 is mainly used to obtain detection data for calculating the leakage rate. In some embodiments, a helium mass spectrometer 20 can be set instead of using the calculation module to measure the leakage rate.

[0018] The upper fixture 1, the sealing cover 3, and the lower fixture 12 construct a device for clamping the battery top - cover sealing ring. A connection groove is provided on the top surface of the lower fixture 12 for connecting with the sealing cover 3. The sealing cover 3 has an inner cavity and covers the top surface of the lower fixture 12. The sealing cover 3 and the lower fixture 12 are connected by a sealing bolt 8, and a first sealing ring 9 is provided on the contact surface between the sealing cover 3 and the lower fixture 12 to ensure the sealing between the two.

[0019] The top of the sealing cover 3 is provided with a fixture connection port, and the upper fixture 1 slides through the fixture connection port and maintains a sliding seal with the sealing cover 3. In this embodiment, the upper fixture 1 is set in an inverted T - shape, and a second sealing ring 2 is provided between the step surface of the upper fixture 1 and the top surface of the inner cavity of the sealing cover 3 to keep the upper fixture 1 and the sealing cover 3 sealed. It should be noted that during the leakage - rate test, the relative sliding between the upper fixture 1 and the sealing cover 3 is only within a very small range, so that the second sealing ring 2 can always play the corresponding sealing role. In some other embodiments, a second sealing ring can also be provided between the side of the upper fixture 1 and the side wall of the sealing cover 3 to achieve sealing. The above - mentioned first sealing ring 9 and second sealing ring 2 are made of fluororubber O - rings, and under the medium pressure less than 10 MPa at normal temperature, the leakage rate ≤ 1×10 -6 Pa·m3 / s. Under high temperature conditions (150 °C), the leakage rate ≤ 1×10 -6 Pa·m 3 / s can be satisfied under the medium pressure of 10 - 15 MPa.

[0020] On the bottom surface of the upper fixture 1, that is, the surface facing the lower fixture 12, a threaded connection groove is provided, and a pressure head 6 is threadedly connected through the threaded connection groove. In order to control the protruding amount of the pressure head when installing different pressure heads 6, a replaceable limit block 5 is also provided in the threaded connection groove. The specifications of the pressure head 6 can be replaced accordingly according to the specifications of the sealing ring 7 to be tested, but this is not necessary. Sealing rings 7 with dimensions smaller than the existing pressure head 6 can all be tested, so the device has good applicability.

[0021] The top surface of the lower fixture 12 is a support surface for placing the sealing ring to be tested. A cavity 10 is provided in the lower fixture 12, and the cavity 10 is connected to a first air passage 22 and a second air passage. The opening of the first air passage 22 is formed on the support surface. The opening of the second air passage is provided on the side surface of the lower fixture 12 to form an air outlet 11. The support surface and the bottom surface of the pressure head 6 (the surface facing the support surface) are the contact surfaces with the sealing ring 7 to be tested, and their surface roughness Ra ≤ 0.4 to prevent leakage during the test.

[0022] An air inlet 4 is provided on the side wall of the sealing cover 3. During the test, the sealing ring 7 to be tested is placed between the support surface of the lower fixture and the pressure head 6. The opening of the first air passage 22 is located at the middle through-hole position of the sealing ring 7. After the sealing cover 3 is connected to the lower fixture 12, a closed gap is formed between the upper fixture 1 and the lower fixture 12 through the sealing of the opening of the first air passage 22 by the pressure head 6 and the sealing ring to be tested, and the air inlet 4 communicates with this closed gap.

[0023] In order to be able to control the ambient temperature of the sealing ring 7 during the test and provide a temperature environment for the leakage rate test, preferably, an environmental chamber 21 is also provided in this embodiment. Among them, the lower part of the upper fixture 1, the whole of the sealing cover 3, and the upper part of the lower fixture 12 are arranged in the environmental chamber 11. Temperature control devices such as liquid nitrogen cooling pipes and heating sheets (not shown in the figure) are provided on the environmental chamber 21 to control the environmental temperature in the environmental chamber 21. The specific setting methods of the liquid nitrogen cooling pipes and heating sheets are conventional setting methods in this field and will not be elaborated. The top of the upper fixture 1 and the bottom of the lower fixture 12 extend out of the environmental chamber 21.

[0024] The gas source 14, the calculation module 17, and the helium mass spectrometer 20 (if adopted) are arranged outside the environmental chamber 21. The gas source 14 is connected to the inlet port 4 on the sealing cover 3 through the outlet valve 13 and a first pipeline. A temperature sensor 15 and a first air pressure sensor 16 are arranged on the first pipeline. A second air pressure sensor 18 is arranged at the outlet port 11 of the lower fixture 12. The temperature sensor 15, the first air pressure sensor 16, and the second air pressure sensor 18 are all electrically connected to the calculation module 17, and the calculation module 17 measures and calculates the leakage rate according to the received sensor information. If the helium mass spectrometer 20 is adopted to measure the leakage rate, the gas source needs to select a helium gas source, and the helium mass spectrometer 20 is connected to the outlet port 11 of the lower fixture 12 through a second pipeline by a valve 19.

[0025] The steps of testing by using the leakage rate testing device for the battery top cover sealing ring are as follows:

[0026] Install the upper fixture 1 and the lower fixture 12 into the universal testing machine through pins. The sealing cover 3 is pre-sleeved on the upper fixture 1. Select a suitable indenter 6 and a limit block 5 and install them on the bottom surface of the upper fixture. Place the sealing ring 7 to be tested between the indenter 6 and the lower fixture 12, and ensure that the opening of the first air passage 22 is in the middle of the sealing ring 7 to be tested.

[0027] Fix and install the sealing cover 3 and the lower fixture 12 to ensure sealing between the two. Apply pressure to the upper fixture 1 and the lower fixture 12 through the universal testing machine to generate sufficient sealing stress on the sealing ring 7 to be tested. Open the outlet valve 13 to inject the leak detection gas medium through the inlet port 4 between the upper fixture 1 and the lower fixture 12, and keep the medium pressure stable. Measure the pressure difference and volume between the inlet port 4 and the outlet port 11 at a specified time interval, and calculate the leakage rate according to the gas state equation.

[0028] If the helium mass spectrometer 20 is adopted for testing, helium gas is used as the leak detection gas medium, and the helium mass spectrometer 20 extracts the helium gas in the cavity 10 of the lower fixture 12 to calculate the leakage rate. After the test by using the helium mass spectrometer 20 is completed, remove the sealing cover 3 and remove the residual helium gas by jetting to ensure the accuracy of the next detection.

Claims

1. A leakage rate testing device for a battery top cover sealing ring, characterized in that, The invention comprises an upper clamp, a sealing cover, a lower clamp, an air source and a computing module, wherein the sealing cover is detachably connected to the lower clamp, a seal is provided between the sealing cover and the lower clamp, a clamp connection port is provided on the top of the sealing cover, the upper clamp is slidably passed through the clamp connection port and maintains a sliding seal with the sealing cover, the upper clamp approaches or moves away from the lower clamp when sliding, the lower clamp is provided with a supporting surface for supporting the sealing ring, a pressure head is provided at one end of the upper clamp facing the supporting surface of the lower clamp, and the sealing cover is provided with a connection port. An air inlet is provided in the gap between the upper clamp and the lower clamp, a cavity is provided in the lower clamp, the cavity is connected to a first air duct and a second air duct, the opening of the first air duct is formed on the supporting surface, and the second air duct forms an air outlet on the lower clamp, the air inlet is connected to the air source through a first pipeline, the first pipeline is provided with a temperature sensor and a first air pressure sensor, the air outlet is provided with a second air pressure sensor, and the calculation module is electrically connected to the temperature sensor, the first air pressure sensor and the second air pressure sensor and is used to calculate the leakage rate.

2. The leakage rate testing device for the battery top cover sealing ring according to claim 1, characterized in that The pressing head is detachably connected to the upper clamp.

3. The leakage rate testing device for the battery top cover sealing ring according to claim 1, wherein, The surface roughness of the side of the indenter facing the supporting surface and the supporting surface is Ra≤0.

4.

4. The leakage rate testing device for the battery top cover sealing ring according to claim 1, wherein It includes an environmental box body, which is provided with a heating and cooling device. A part of the upper clamp, the sealing cover and a part of the lower clamp are arranged inside the environmental box body, and one end of the upper clamp facing away from the lower clamp and one end of the lower clamp facing away from the upper clamp are arranged outside the environmental box body.

5. The leakage rate testing device for the battery top cover sealing ring according to claim 4, wherein, The ambient temperature in the environmental box is -40°C to 150°C.

6. A leakage rate testing device for a battery top cover sealing ring, characterized in that, The cam is connected to the lower clamp by a sealing mechanism, and the sealing mechanism is connected to the upper clamp by a sealing mechanism, wherein the sealing mechanism is connected to the lower clamp by a sealing mechanism, and the sealing mechanism is connected to the lower clamp by a sealing mechanism.

7. The leakage rate testing device for the battery top cover sealing ring according to claim 6, characterized in that, The pressing head is detachably connected to the upper clamp.

8. The leakage rate testing device for the battery top cover sealing ring according to claim 6, characterized in that, The surface roughness of the side of the indenter facing the supporting surface and the supporting surface is Ra≤0.

4.

9. The leakage rate testing device for the battery top cover sealing ring according to claim 6, characterized in that, It includes an environmental box body, which is provided with a heating and cooling device. A part of the upper clamp, the sealing cover and a part of the lower clamp are arranged inside the environmental box body, and one end of the upper clamp facing away from the lower clamp and one end of the lower clamp facing away from the upper clamp are arranged outside the environmental box body.

10. The leakage rate testing device for the battery top cover sealing ring according to claim 9, characterized in that, The ambient temperature inside the environmental chamber is -40°C to 150°C.

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