Helium detection tool for detecting sealing performance of weld joint of battery shell and detection method of helium detection tool

Abstract

The invention relates to a helium detection tool for battery shell welding seam sealing performance detection and a detection method thereof, and relates to the technical field of product sealing performance testing equipment. The helium detection tool comprises a base; a test support column is arranged on the base; an air inlet channel is formed in the test supporting column, and an air inlet communicated with the air inlet channel is formed in the lower end of the test supporting column; one side of the test supporting column is provided with a plurality of air outlet holes which are distributed along the axial direction of the test supporting column, and all the air outlet holes are communicated with the air inlet channel; a detection stand column is also arranged on one side of the test support column on the base; the side face of the detection stand column is provided with an air exhaust groove in the axial direction of the detection stand column, and a notch of the air exhaust groove faces the air outlet hole. And the upper end of the detection stand column is provided with an extraction opening which is used for being connected with a mass spectrometer and is communicated with the extraction groove. The device achieves the technical effects of accurately detecting the sealing performance of the weld joint of the battery shell, being convenient to operate, and improving the detection efficiency and accuracy.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of product sealing test equipment, in particular to a helium detection tool for battery shell weld sealing detection and a detection method thereof. BACKGROUND

[0002] In the field of battery manufacturing technology, steel or aluminum or zinc shell as a key packaging component of battery core is self-evident. With the continuous development of the battery industry, higher requirements are put forward for the safety and service life of the battery, and the sealing performance of the battery shell directly affects the two key indicators. In the battery production process, the manufacturing and sealing detection of the battery shell become the key link to ensure the quality of the battery, and high-precision automatic detection technology is of great significance to improve the production efficiency and quality of the battery.

[0003] Due to the characteristics of helium gas, such as no harm to human body and natural environment, no combustion, safe operation, and no chemical reaction with the detected object, the helium leak detection process is one of the main leak detection methods for battery structural parts. By using the helium leak detection process to detect whether the sealing performance of the corresponding battery shell is good, it plays an irreplaceable role in the production process of battery structural parts.

[0004] In the field of new energy vehicles, medium and large electric equipment, etc., the battery shell usually includes a cylinder for containing the chemical substances of the battery core and an end cover for closing the two ends of the cylinder; in the related technical scheme, the square cylinder of the battery shell is manufactured by four times of bending integrated forming process, and finally a weld on one side of the square cylinder is needed for welding sealing, which becomes a leak point and is the focus of attention for sealing detection of the battery shell.

[0005] The traditional general-purpose helium detection equipment mainly detects the sealing performance of various workpieces according to a relatively broad detection process. Since there is no specific design for this type of square cylinder of the battery shell, it is difficult to accurately position the weld position during detection, and it is also impossible to efficiently detect according to the special structure of the battery shell. At the same time, due to the inability to accurately position the detection, false positives are likely to occur, resulting in inaccurate detection results and affecting the quality and efficiency of battery production. SUMMARY

[0006] In order to improve the accuracy, reliability and efficiency of special battery shell sealing helium detection, the application provides a helium detection tool for battery shell weld sealing detection and a detection method thereof.

[0007] In a first aspect, the helium detection tool for battery shell weld sealing detection provided by the application adopts the following technical scheme: A helium detection tool for battery shell weld sealing detection, comprising a base; The base is provided with a test support column for supporting the battery casing; the interior of the test support column has an air intake channel along the axial direction of the test support column, and the lower end of the test support column has an air inlet for connecting to an external air source and communicating with the air intake channel. The test support column has several air outlets arranged along the axial direction of the test support column on one side, and all the air outlets are connected to the air inlet channel. A detection column is also provided on one side of the test support column on the base; the side of the detection column is provided with a suction groove along the axial direction of the detection column, and the opening of the suction groove faces the air outlet; the upper end of the detection column has a suction port for connecting to a mass spectrometer and communicating with the suction groove. Above the test support column is a pressure plate that can move up and down repeatedly.

[0008] In this application, the detection column and the test support column are arranged parallel to each other, forming a detection area between them for detecting the weld seam in the middle of the battery casing. The evacuation groove of the detection column is used to capture helium gas escaping from the weld seam. In use, the open end of the battery casing is inserted downwards into the test support column of the helium detection fixture, with the welded side of the battery casing facing the vent side of the test support column. The battery casing is pressed down by the pressure plate, forming a sealed connection between the open end of the battery casing and the base of the helium detection fixture, thus creating a sealed cavity between the battery casing and the test support column. The inlet of the test support column is connected to an external helium source through a pipe. The external helium source enters the inlet channel through the inlet of the test support column and is directionally sprayed onto the weld area of ​​the battery casing through the vent on the test support column. The suction groove of the test support column is connected to the mass spectrometer through the suction port at its upper end. After the mass spectrometer is started, a negative pressure field is established in the suction groove of the detection column. The escaping helium enters the mass spectrometer for analysis through the suction groove and suction port. The weld sealing level is determined based on the mass spectrometer signal intensity.

[0009] By adopting the above technical solution, a test support column supports the battery casing, and the battery casing is fitted onto the test support column, forming a sealed cavity between the two. A pressure plate can move up and down to press the battery casing into the sealed cavity, achieving high-precision and high-efficiency testing of the weld sealing performance of the battery casing. This application utilizes a specialized tooling design, specifically the structural and positional layout of the test support column and the test column, with the helium gas outlet directly facing the leak-prone weld area, achieving high-precision and high-efficiency testing of the weld sealing performance of a specific battery casing in the middle of one side. This improves work efficiency and significantly reduces the false positive rate.

[0010] Optionally, one side of the test support column has a through groove extending through both ends along its axial direction, and the air outlets are evenly spaced at the bottom of the through groove.

[0011] By adopting the above technical solution, a through groove extending axially through both ends is set on one side of the test support column, and the air outlets are evenly spaced at the bottom of the groove. This allows helium gas to be sprayed more evenly from the air outlets to the weld area of ​​the battery casing, improving the accuracy and reliability of the test and ensuring smooth, uniform and stable airflow.

[0012] Optionally, the air intake channel is located at the center of the test support column and extends through both ends of the test support column along its axial direction. The top of the test support column has several protrusions around the air intake channel. A flow passage is formed between adjacent protrusions and between the protrusions and the outer edge of the test support column. The flow passage connects the air intake channel and the through groove.

[0013] By adopting the above technical solution, when the battery casing is inserted into the test support column, the closed end of the battery casing contacts several protrusions at the top of the test support column. At this time, there is a certain airflow space between the closed end of the square shell and the top of the test support column, so that helium can come out from the top of the test support column and ensure stable gas pressure, thereby achieving high-precision and high-efficiency detection of the sealing performance of the battery casing weld.

[0014] Optionally, the test support column and the detection column are arranged side by side at intervals, the air extraction groove is located at the middle position of the width direction of the side of the detection column, the through groove is located at the middle position of the width direction of the side of the test support column, and the air extraction groove is directly opposite the through groove.

[0015] By adopting the above technical solution, helium gas can be precisely and directionally injected into the weld area of ​​the battery casing, and helium gas escaping from the weld can be precisely captured, thereby achieving high-precision detection of the sealing performance of the battery casing weld.

[0016] Optionally, the base includes a mounting boss, and the test support column and the detection column are both vertically fixed on the mounting boss; The mounting boss has a horizontal connecting channel inside. One end of the connecting channel is connected to the air inlet at the lower end of the test support column, and the other end of the connecting channel is connected to an external air source pipeline.

[0017] By adopting the above technical solution, the stability and relative positional accuracy of the test support column and the detection column are ensured. The horizontal connecting hole inside the mounting boss enables convenient and reliable connection between the external helium gas source pipe and the gas inlet of the test support column, providing a stable channel for the delivery of helium during the detection process, which helps to achieve high-precision and high-efficiency detection of the sealing performance of the battery casing welds. At the same time, it facilitates the assembly and connection of the entire device.

[0018] Optionally, the mounting boss has a mounting hole on its upper side, and a mounting pad is embedded in the mounting hole; the test support column is disposed on the mounting pad; a connecting hole is formed in the middle of the mounting pad; the air inlet at the lower end of the test support column and the connecting channel are respectively connected to the upper and lower ends of the connecting hole.

[0019] By adopting the above technical solution, the mounting pad facilitates the installation and positioning of the test support column, enabling the air inlet at the lower end of the test support column and the connecting hole inside the mounting boss to achieve stable connection through the connecting hole in the middle of the mounting pad. This ensures that helium gas from an external gas source can smoothly enter the air inlet channel of the test support column through the connecting hole and the connecting hole, ensuring the stability of helium gas delivery and thus improving the accuracy and reliability of the battery casing weld sealing test. At the same time, it also helps to seal the open end of the battery casing when the pressure plate presses down on the battery casing.

[0020] Optionally, the base includes a mounting base plate, on which a plurality of first connecting columns are fixedly mounted. A crossbeam is provided at the upper end of each of the first connecting columns, and a top plate is mounted on the crossbeam. The top plate is located above the test support column and the detection column. A vertically downward first telescopic drive member is fixedly mounted on the top plate, and the pressure plate is fixedly connected to the output shaft of the first telescopic drive member.

[0021] By adopting the above technical solution, the pressure plate can move up and down reciprocally above the test support column and the test column, thereby pressing the battery casing tightly onto the base and forming a sealed cavity between the battery casing and the test support column. This provides a stable testing environment for subsequent testing of the sealing performance of the battery casing welds, which helps to improve the accuracy and reliability of the testing.

[0022] Optionally, a slide rail is provided on the crossbeam, and the top plate is slidably connected to the slide rail by a slider; A second connecting column is fixed on the base or on one side of the base; a mounting block is fixed on the upper end of the second connecting column, and a second telescopic drive member is fixed on the mounting block facing the top plate. The middle part of one side of the top plate is fixedly connected to the output shaft of the second telescopic drive member, and the second telescopic drive member can drive the top plate to move laterally back and forth on the slide rail.

[0023] By adopting the above technical solution, when testing the sealing performance of the battery casing weld, the top plate can slide on the slide rail of the crossbeam via a slider. The second telescopic drive component drives the top plate to move laterally back and forth on the slide rail, so that the pressure plate on the top plate can move horizontally to directly above the battery casing. This allows for flexible adjustment of the horizontal position of the pressure plate, facilitating the subsequent downward movement of the pressure plate to press the battery casing, thereby improving the convenience and automation of the testing operation.

[0024] Optionally, the end of the crossbeam or the slide rail is further provided with a limiting block, which is used to limit the extreme position of the top plate on the slide rail.

[0025] By adopting the above technical solution, setting a limiting block at the end of the crossbeam or slide rail can limit the extreme position of the top plate on the slide rail, avoid excessive movement of the top plate, ensure the structural stability and safety of the helium inspection tool, and help to achieve stable detection of the sealing performance of the battery casing weld.

[0026] Secondly, the detection method for testing the sealing performance of battery casing welds using the aforementioned helium testing fixture provided in this application adopts the following technical solution: A method for inspecting the sealing performance of weld seams in battery casings using a helium inspection fixture, the method comprising the following steps: S1. Insert the open end of the battery casing downwards into the test support column of the helium testing fixture, so that the closed end of the battery casing contacts the top of the test support column; and the side of the battery casing with the weld seam faces the side of the test support column with the gas outlet. S2. The pressure plate moves horizontally to directly above the battery casing; S3. The pressure plate moves downward to press the battery casing, so that the open end of the battery casing forms a sealed connection with the base of the helium testing fixture, thereby forming a sealed cavity between the battery casing and the test support column; S4. An external helium gas source enters the air intake channel through the air inlet of the test support column and is directionally sprayed onto the weld area of ​​the battery casing through the air outlet on the test support column. S5. The gas extraction groove of the detection column is connected to the mass spectrometer through the gas extraction port at its upper end. After the mass spectrometer is started, a negative pressure field is established in the gas extraction groove of the detection column, and the escaping helium gas enters the mass spectrometer for analysis through the gas extraction groove and the gas extraction port. S6. Determine the weld sealing level based on the mass spectrometer signal intensity.

[0027] By adopting the above technical solution, the battery casing is placed on the test support column with the weld seam facing the vent hole. The pressure plate presses the battery casing to form a sealed cavity. Helium gas is injected directionally into the weld seam area through the inlet channel and the vent hole. The suction groove of the test column establishes a negative pressure field to capture the escaped helium gas and enter it for mass spectrometry analysis. Finally, the weld seam sealing level is determined based on the mass spectrometer signal intensity. This achieves high-precision automatic detection of the sealing performance of the battery casing weld seam and solves the problems of low detection efficiency and high false judgment rate of existing general-purpose helium detection equipment.

[0028] In summary, this application includes at least one of the following beneficial technical effects: 1. The dedicated helium testing fixture structure design in this application can achieve high-precision testing of the sealing performance of the central weld seam on one side of a specific battery casing, solving the problem of high misjudgment rate caused by the lack of fixtures for special structures in existing general-purpose equipment.

[0029] 2. The layout and structure of the test support column and the detection column in this application can directionally inject helium gas into the weld area and effectively capture the helium gas escaping from the weld, thereby improving detection efficiency and solving the problem of low detection efficiency of existing general-purpose equipment.

[0030] 3. The protruding design at the top of the test support column in this application ensures that helium gas can exit from the top of the test support column through the air inlet, ensuring stable gas pressure and helping to improve the accuracy of the test. Attached Figure Description

[0031] Figure 1 This is a three-dimensional structural diagram of the battery casing.

[0032] Figure 2 This is a first three-dimensional structural schematic diagram of the helium detection tooling in this application.

[0033] Figure 3 This is a schematic diagram of the second three-dimensional structure of the helium detection fixture in this application.

[0034] Figure 4 This is a three-dimensional structural schematic diagram of the test support column in the helium detection fixture of this application.

[0035] Figure 5 This is a schematic diagram of the second three-dimensional structure of the test support column in the helium detection fixture of this application.

[0036] Figure 6 This is a partial structural schematic diagram of the helium detection tooling in this application.

[0037] Figure 7 This is a three-dimensional structural diagram of the mounting boss and detection column in the helium detection tooling of this application.

[0038] Figure 8 This is a cross-sectional structural diagram of the helium detection tooling of this application.

[0039] In the picture: 10. Base; 11. Mounting boss; 111. Connecting channel; 112. Mounting hole; 113. Mounting pad; 1131. Connecting hole; 12. Mounting base plate; 13. First connecting column; 14. Second connecting column; 15. Crossbeam; 16. Top plate; 17. Slide rail; 18. Mounting block; 19. Limiting block; 20. Test support column; 21. Air intake channel; 22. Air inlet; 23. Air outlet; 24. Through groove; 25. Protrusion; 26. Flow channel; 30. Inspection column; 31. Air extraction groove; 32. Air extraction port; 40. Pressure plate; 50. First telescopic drive component; 60. Second telescopic drive component; 70. Battery casing; 71. Weld seam; 80. Slider. Detailed Implementation

[0040] The following will be combined with the appendix Figure 1 - Appendix Figure 8 The technical solutions in the embodiments of the present invention are clearly and completely described herein. The described embodiments are only possible technical implementations of the present invention and not all possible implementations. Those skilled in the art can obtain other embodiments in conjunction with the embodiments of the present invention without creative effort, and these embodiments are also within the protection scope of the present invention.

[0041] The helium testing fixture and method for inspecting the seal of weld 71 in the battery casing 70 described in this application are for sealing inspection of a specific battery casing 70, and refer to... Figure 1 As shown, the battery casing 70 includes a cylindrical body made of steel, aluminum, or zinc. One end of the cylindrical body is closed, and the other end has an opening. The cross-section of the cylindrical body is rectangular, that is, the battery casing 70 is a square shell. The square cylindrical body of the battery casing 70 is manufactured by a four-fold bending integral forming process. Finally, an interface is formed in the center of one side of the square cylindrical body, and a sealing connection is made by welding. This will form a weld seam 71 in the center of one side of the square cylindrical body.

[0042] Example 1

[0043] Reference Figure 2 and Figure 3 As shown, the helium testing fixture for testing the sealing performance of the battery casing 70 in this application includes a base 10, a test support column 20, and a test column 30. The base 10 includes a mounting base plate 12 and a mounting boss 11, with the mounting boss 11 fixed on the mounting base plate 12. A plurality of first connecting columns 13 are fixed on the mounting base plate 12, preferably four first connecting columns 13 in this embodiment, arranged in a rectangular array. A pair of parallel and spaced crossbeams 15 are provided at the upper end of the first connecting columns 13, and a top plate 16 is mounted on the two crossbeams 15.

[0044] Reference Figure 2 and Figure 3 As shown, both the test support column 20 and the test column 30 are vertically fixed on the mounting boss 11. The test support column 20 is used to support the battery casing 70, meaning the battery casing 70 can be fitted onto the test support column 20. (Refer to...) Figure 4 and Figure 5As shown, the test support column 20 has an air intake channel 21 running along its axial direction. The lower end of the test support column 20 has an air inlet 22 for connecting to an external air source and communicating with the air intake channel 21. One side of the test support column 20 has several air outlets 23 arranged along its axial direction, all of which communicate with the air intake channel 21. Furthermore, the air intake channel 21 is located at the center of the test support column 20 and extends through both ends of the test support column 20 along its axial direction. One side of the test support column 20 has a through groove 24 extending through both ends along its axial direction. The air outlets 23 are evenly spaced at the bottom of the through groove 24, so that helium gas is sprayed more evenly from the air outlets 23 to the weld seam 71 area of ​​the battery casing 70, improving the accuracy and reliability of the test. The top of the test support column 20 has several protrusions 25 surrounding the air inlet channel 21. A flow channel 26 is formed between adjacent protrusions 25 and between the protrusions 25 and the outer edge of the test support column 20. The flow channel 26 connects the air inlet channel 21 and the through groove 24. The above structure ensures smooth, uniform and stable airflow.

[0045] Reference Figure 6 and Figure 7 As shown, the detection column 30 is located on one side of the test support column 20. The side of the detection column 30 is provided with a suction groove 31 along the axial direction of the detection column 30, and the groove opening of the suction groove 31 faces the air outlet 23. The upper end of the detection column 30 has a suction port 32 for connecting to the mass spectrometer and communicating with the suction groove 31.

[0046] In this application, the test support column 20 and the detection column 30 are arranged side by side at intervals. The suction groove 31 is located in the middle of the width direction of the side of the detection column 30, and the through groove 24 is located in the middle of the width direction of the side of the test support column 20. The suction groove 31 is directly opposite the through groove 24. This allows for precise and directional injection of helium gas into the weld seam 71 area of ​​the battery casing 70, while accurately capturing the helium gas escaping from the weld seam 71, thereby achieving high-precision detection of the sealing performance of the weld seam 71 of the battery casing 70.

[0047] Reference Figure 2 and Figure 3As shown, a slide rail 17 is provided on the crossbeam 15, and the top plate 16 is slidably connected to the slide rail 17 via a slider. The top plate 16 is located above the test support column 20 and the detection column 30. A vertically downward first telescopic drive member 50 is fixed on the top plate 16, and a pressure plate 40 is fixedly connected to the output shaft of the first telescopic drive member 50. The pressure plate 40 can move up and down reciprocally under the drive of the first telescopic drive member 50. A second connecting column 14 is fixed on the base 10 or on one side of the base 10. A mounting block 18 is fixed at the upper end of the second connecting column 14, and a second telescopic drive member 60 facing the top plate 16 is fixed on the mounting block 18. The middle part of one side of the top plate 16 is fixedly connected to the output shaft of the second telescopic drive member 60, and the second telescopic drive member 60 can drive the top plate 16 to move laterally reciprocally on the slide rail 17. In this application, the first telescopic drive member 50 and the second telescopic drive member 60 can be a combination structure of a hydraulic cylinder, a pneumatic cylinder, or a motor screw. With the above structure, the pressure plate 40 can move back and forth left and right and up and down above the test support column 20 and the test column 30, so as to accurately press the battery casing 70 onto the base 10, so that the battery casing 70 and the test support column 20 form a sealed cavity, providing a stable testing environment for subsequent testing of the sealing performance of the weld 71 of the battery casing 70, which helps to improve the accuracy and reliability of the test.

[0048] In this application, a limiting block 19 is also provided at the end of the crossbeam 15 or the slide rail 17. The limiting block 19 is used to limit the extreme position of the top plate 16 on the slide rail 17. Providing a limiting block 19 at the end of the crossbeam 15 or the slide rail 17 can limit the extreme position of the top plate 16 on the slide rail 17, avoid excessive movement of the top plate 16, ensure the structural stability and safety of the helium inspection fixture, and help to achieve stable detection of the sealing performance of the weld 71 of the battery casing 70.

[0049] Reference Figure 6 and Figure 8As shown, the mounting boss 11 has a horizontal connecting channel 111 inside. One end of the connecting channel 111 is connected to the air inlet 22 at the lower end of the test support column 20, and the other end of the connecting channel 111 is connected to an external gas source pipeline. This facilitates reliable connection between the external helium gas source pipeline and the air inlet 22 of the test support column 20, providing a stable channel for the delivery of helium during the testing process. The upper side of the mounting boss 11 has a mounting hole 112, and a mounting pad 113 is embedded in the mounting hole 112. The test support column 20 is set on the mounting pad 113. A connecting hole 1131 is opened in the middle of the mounting pad 113. The air inlet 22 at the lower end of the test support column 20 and the connecting channel 111 are respectively connected to the upper and lower ends of the connecting hole 1131. The mounting pad 113 can be made of rubber. Stable docking is achieved through the connecting hole 1131 in the middle of the mounting pad 113, ensuring that helium gas from the external gas source can smoothly enter the air intake channel 21 of the test support column 20 through the connecting channel 111 and the connecting hole 1131, ensuring the stability of helium gas delivery, thereby improving the accuracy and reliability of the sealing test of the weld 71 of the battery casing 70; at the same time, it can also help to close the opening end of the battery casing 70 when the pressure plate 40 presses down on the battery casing 70.

[0050] The implementation principle is as follows: In this application, the detection column 30 and the test support column 20 are arranged parallel to each other, forming a detection area for detecting the weld 71 in the middle of the battery casing 70. The suction groove 31 of the detection column 30 is used to capture the helium gas escaping from the weld 71. In use, the open end of the battery casing 70 is inserted downwards into the test support column 20 of the helium detection fixture, with the side of the battery casing 70 with the weld 71 facing the side of the test support column 20 with the gas outlet; when the battery casing 70 is inserted onto the test support column 20, the pressure plate 40 moves downwards to press the battery casing 70, so that the open end of the battery casing 70 forms a sealed connection with the base 10 of the helium detection fixture, thereby forming a sealed cavity between the battery casing 70 and the test support column 20; the closed end of the battery casing 70 contacts several protrusions 25 at the top of the test support column 20, at which time there is a certain airflow space between the closed end of the casing and the top of the test support column 20. The air inlet 22 of the test support column 20 is connected to an external helium source through a pipe. The external helium source enters the air intake channel 21 through the air inlet 22 of the test support column 20 and is directionally sprayed to the weld seam 71 area of ​​the battery casing 70 through the air outlet 23 on the test support column 20. Helium can also come out from the top of the test support column 20, thus ensuring stable gas pressure. The air extraction groove 31 of the test support column 20 is connected to the mass spectrometer through the air extraction port 32 at its upper end. After the mass spectrometer is started, a negative pressure field is established in the air extraction groove 31 of the test column 30. The escaping helium enters the mass spectrometer for analysis through the air extraction groove 31 and the air extraction port 32. The sealing level of the weld seam 71 is determined according to the signal strength of the mass spectrometer, thereby determining whether the product meets the requirements.

[0051] This application utilizes a specialized tooling design, specifically the structural and positional layout of the test support column 20 and the detection column 30, with the helium gas outlet directly facing the leak-prone weld seam 71 area. This enables high-precision and high-efficiency testing of the sealing performance of the weld seam 71 in the middle of one side of a specific battery casing 70. This improves work efficiency and significantly reduces the false positive rate.

[0052] Example 2

[0053] This embodiment provides a method for testing the sealing performance of the weld 71 of the battery casing 70 using the aforementioned helium testing fixture. The method includes the following steps: S1. Insert the open end of the battery casing 70 downwards into the test support column 20 of the helium testing fixture, so that the closed end of the battery casing 70 contacts the top of the test support column 20; and the side of the battery casing 70 with the weld 71 faces the side of the test support column 20 with the vent. S2, the pressure plate 40 moves horizontally to directly above the battery casing 70; S3. The pressure plate 40 moves downward to press the battery casing 70, so that the open end of the battery casing 70 forms a sealed connection with the base 10 of the helium testing fixture, thereby forming a sealed cavity between the battery casing 70 and the test support column 20. S4. An external helium gas source enters the air intake channel 21 through the air inlet 22 of the test support column 20, and is directionally sprayed into the weld seam 71 area of ​​the battery casing 70 through the air outlet 23 on the test support column 20. S5. The gas extraction groove 31 of the detection column 30 is connected to the mass spectrometer through the gas extraction port 32 at its upper end. After the mass spectrometer is started, a negative pressure field is established in the gas extraction groove 31 of the detection column 30, and the escaped helium gas enters the mass spectrometer for analysis through the gas extraction groove 31 and the gas extraction port 32. S6. Determine the sealing level of weld 71 based on the mass spectrometer signal intensity.

[0054] The implementation principle is as follows: The battery casing 70 is placed on the test support column 20 with the weld 71 facing the vent 23. The pressure plate 40 presses the battery casing 70 to form a sealed cavity. Helium gas is injected directionally into the weld 71 area through the inlet channel 21 and the vent 23. The suction groove 31 of the detection column 30 establishes a negative pressure field to capture the escaped helium gas and enter the mass spectrometer for analysis. Finally, the sealing level of the weld 71 is determined according to the signal intensity of the mass spectrometer. This achieves high-precision automatic detection of the sealing performance of the weld 71 of the battery casing 70, and solves the problems of low detection efficiency and high misjudgment rate of existing general-purpose helium detection equipment.

[0055] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be covered within the scope of protection of this application.

Claims

1. A helium testing fixture for inspecting the sealing performance of weld seams in battery casings, comprising a base (10); Its features are, The base (10) is provided with a test support column (20) for supporting the battery casing (70); the interior of the test support column (20) has an air intake channel (21) along the axial direction of the test support column (20), and the lower end of the test support column (20) has an air inlet (22) for connecting to an external air source and communicating with the air intake channel (21). The test support column (20) has several air outlets (23) arranged along the axial direction of the test support column (20) on one side, and all the air outlets (23) are connected to the air inlet channel (21). A detection column (30) is also provided on one side of the test support column (20) on the base (10); the side of the detection column (30) is provided with a suction groove (31) along the axial direction of the detection column (30), and the opening of the suction groove (31) faces the air outlet (23); the upper end of the detection column (30) has a suction port (32) for connecting to the mass spectrometer and communicating with the suction groove (31); Above the test support column (20) is a pressure plate (40) that can move up and down.

2. The helium testing fixture for detecting the sealing performance of battery casing welds according to claim 1, characterized in that, The test support column (20) has a through groove (24) extending through both ends along its axial direction on one side, and the air outlets (23) are evenly spaced at the bottom of the through groove (24).

3. The helium testing fixture for detecting the sealing performance of battery casing welds according to claim 2, characterized in that, The air intake channel (21) is located at the center of the test support column (20) and extends through both ends of the test support column (20) along its axial direction. The top of the test support column (20) has a number of protrusions (25) around the air intake channel (21). A flow passage (26) is formed between adjacent protrusions (25) and between the protrusions (25) and the outer edge of the test support column (20). The flow passage (26) connects the air intake channel (21) and the through groove (24).

4. The helium testing fixture for detecting the sealing performance of battery casing welds according to claim 2 or 3, characterized in that, The test support column (20) and the detection column (30) are arranged side by side with intervals. The air extraction groove (31) is located at the middle of the width direction of the side of the detection column (30). The through groove (24) is located at the middle of the width direction of the side of the test support column (20). The air extraction groove (31) is directly opposite the through groove (24).

5. The helium testing fixture for detecting the sealing performance of weld seams in battery casings according to claim 1, 2, or 3, characterized in that, The base (10) includes a mounting boss (11), and the test support column (20) and the detection column (30) are both vertically fixed on the mounting boss (11); The mounting boss (11) has a horizontal connecting channel (111) inside. One end of the connecting channel (111) is connected to the air inlet (22) at the lower end of the test support column (20), and the other end of the connecting channel (111) is connected to an external air source pipeline.

6. The helium testing fixture for detecting the sealing performance of battery casing welds according to claim 5, characterized in that, The mounting boss (11) has a mounting hole (112) on its upper side, and a mounting pad (113) is embedded in the mounting hole (112); the test support column (20) is set on the mounting pad (113); a connecting hole (1131) is opened in the middle of the mounting pad (113); the air inlet (22) at the lower end of the test support column (20) and the connecting channel (111) are respectively connected to the upper and lower ends of the connecting hole (1131).

7. The helium testing fixture for detecting the sealing performance of weld seams in battery casings according to claim 1, 2, or 3, characterized in that, The base (10) includes a mounting base plate (12), on which a plurality of first connecting columns (13) are fixedly mounted. A crossbeam (15) is provided at the upper end of the first connecting columns (13), and a top plate (16) is mounted on the crossbeam (15). The top plate (16) is located above the test support column (20) and the detection column (30). A vertically downward first telescopic drive member (50) is fixedly mounted on the top plate (16), and the pressure plate (40) is fixedly connected to the output shaft of the first telescopic drive member (50).

8. The helium testing fixture for detecting the sealing performance of weld seams in battery casings according to claim 7, characterized in that, A slide rail (17) is provided on the crossbeam (15), and the top plate (16) is slidably connected to the slide rail (17) by a slider (80); A second connecting column (14) is fixed on the base (10) or on one side of the base (10); an mounting block (18) is fixed at the upper end of the second connecting column (14), and a second telescopic drive member (60) facing the top plate (16) is fixed on the mounting block (18). The middle part of one side of the top plate (16) is fixedly connected to the output shaft of the second telescopic drive member (60), and the second telescopic drive member (60) can drive the top plate (16) to move laterally back and forth on the slide rail (17).

9. The helium testing fixture for detecting the sealing performance of battery casing welds according to claim 8, characterized in that, The end of the crossbeam (15) or the slide rail (17) is also provided with a limiting block (19), which is used to limit the extreme position of the top plate (16) on the slide rail (17).

10. A method for testing the sealing performance of weld seams in a battery casing (70) using the helium testing fixture described in any one of claims 1-9, characterized in that, The detection method includes the following steps: S1. Insert the open end of the battery casing (70) downwards into the test support column (20) of the helium testing fixture, so that the closed end of the battery casing (70) contacts the top of the test support column (20); and the side of the battery casing (70) with the weld is facing the side of the test support column (20) with the gas outlet. S2, The pressure plate (40) moves horizontally to directly above the battery casing (70); S3. The pressure plate (40) moves downward to press the battery casing (70) so that the open end of the battery casing (70) forms a sealed connection with the base (10) of the helium testing fixture, thereby forming a sealed cavity between the battery casing (70) and the test support column (20). S4. An external helium gas source enters the air intake channel (21) through the air inlet (22) of the test support column (20) and is directionally sprayed to the weld area of ​​the battery casing (70) through the air outlet (23) on the test support column (20). S5. The gas extraction groove (31) of the detection column (30) is connected to the mass spectrometer through the gas extraction port (32) at its upper end. After the mass spectrometer is started, a negative pressure field is established in the gas extraction groove (31) of the detection column (30). The escaping helium gas enters the mass spectrometer for analysis through the gas extraction groove (31) and the gas extraction port (32). S6. Determine the weld sealing level based on the mass spectrometer signal intensity.

Images