Spot welding strength detection device

Abstract

The utility model discloses a spot welding firmness detection device, including pressing plate, fixed part, drive structure and force measuring piece, and the pressing plate is used for covering and flattening the copper foil and copper mesh spot welding workpiece of measuring, and the pressing plate is provided with the through accommodating hole, and the fixed part is used for passing through the accommodating hole and the copper mesh is hooked, and the drive structure is connected fixed part, is used for driving fixed part movement to make copper mesh and copper foil separate, and the force measuring piece is connected fixed part, is used for detecting the tension, and the technical problem of alleviating copper foil in the test extremely easy to be pulled apart or the technical problem of tearing and affecting detection.

Description

Technical Field

[0001] This utility model relates to the field of spot welding testing technology, and specifically to a spot weld strength testing device. Background Technology

[0002] Currently, in the manufacturing process of electrical connectors, electronic packages, and conductive components, copper mesh is often fixed to a copper foil substrate by spot welding to achieve both conductive and mechanical fixation functions. To ensure the quality of spot welding, tensile testing is usually required to assess the bond strength of the weld joint. Existing testing methods mainly rely on general-purpose tensile testing machines or handheld tensile testers to perform tensile tests, determining the weld quality by measuring the force at which the weld joint breaks.

[0003] However, when performing tensile testing on copper mesh and copper foil structures, traditional testing usually uses double hooks or double clamps to stretch both ends of the sample. However, due to the extremely thin thickness of the copper foil (usually less than 0.05 mm) and its extremely low mechanical strength, the stress is easily concentrated in the weak areas of the copper foil, making it very easy to be torn or broken during the testing process, causing the test to be unable to continue or the results to be distorted.

[0004] Therefore, there is an urgent need for a testing device that can effectively protect the copper foil substrate and prevent the copper foil from being torn during tensile testing, while also ensuring testing accuracy and ease of operation, in order to meet the reliability testing requirements of copper foil and copper mesh spot welds. Utility Model Content

[0005] The purpose of this invention is to overcome the above-mentioned technical deficiencies and propose a spot weld strength testing device to solve the technical problem that copper foil is easily torn or broken during testing, affecting the detection.

[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution: In a first aspect, this utility model provides a spot weld strength testing device, comprising: a pressure plate for covering and flattening the spot welded workpiece of copper foil and copper mesh to be tested, the pressure plate having a through clearance hole; a fixing member for passing through the clearance hole and hooking the copper mesh; a driving structure connected to the fixing member for driving the fixing member to move so that the copper mesh and copper foil are separated; and a force measuring member connected to the fixing member for detecting tensile force.

[0007] In some embodiments, the cross-sectional area of ​​the clearance hole does not exceed 15 percent of the area of ​​the copper mesh.

[0008] In some embodiments, the spot weld strength testing device further includes a bushing nested within a relief hole for adjusting the effective diameter of the relief hole.

[0009] In some embodiments, the clearance hole or bushing edge is provided with an elastic layer.

[0010] In some embodiments, the fastener is a barb structure, a mechanical gripper, or a vacuum suction cup.

[0011] In some embodiments, the edge of the pressure plate is provided with a locking component for fixing the position of the workpiece.

[0012] In some embodiments, the spot weld strength testing device further includes a bracket, which is fixed to one side of the pressure plate, and the drive structure is mounted on the bracket.

[0013] In some embodiments, the drive structure includes a guide and a drive member, the guide being fixed to the bracket, and the drive member driving the fixed member to move along the guide.

[0014] In some embodiments, the guide extends perpendicular to the plane of the copper foil.

[0015] In some embodiments, the support includes at least one support column that is telescopic in the direction perpendicular to the copper foil.

[0016] Compared with existing technologies, the spot weld strength testing device provided by this utility model, through the planar support of the pressure plate on the copper foil, can evenly distribute the local load during the tensile process, preventing stress concentration that could lead to copper foil breakage or deformation. Simultaneously, the clearance holes on the pressure plate define the area of ​​application of the tensile force, ensuring that the tensile force is transmitted to the weld point only through the connection between the fixing component and the copper mesh, avoiding stress on non-test areas and ensuring the uniformity and accuracy of the tensile force loading at the weld point. Through the combination of the pressure plate and clearance holes, this application allows the force measuring component to monitor changes in tensile force in real time, accurately reflecting the bonding strength of the weld point and ensuring the accuracy and repeatability of the test data. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a spot weld strength testing device provided in an embodiment of this utility model; Figure 2 This is a schematic diagram of a spot weld strength testing device provided in an embodiment of this utility model; Figure 3 This is a schematic diagram of the structure of a pressure plate provided in an embodiment of this utility model; Figure 4 This is a schematic diagram of the pressure plate and support column structure provided in an embodiment of this utility model.

[0018] Explanation of reference numerals in the attached figures: 10. Pressure plate; 11. Clearance hole; 20. Fixing component; 30. Drive structure; 31. Guide component; 32. Drive component; 40. Force measuring component; 50. Bushing; 60. Elastic layer; 70. Locking assembly; 80. Bracket; 81. Support column; 90. Workpiece; 91. Copper mesh; 92. Copper foil. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0020] In order to solve the technical problem that copper foil 92 is easily torn or broken during testing in the prior art, which affects the detection, this utility model provides a spot weld strength testing device, which can effectively protect the copper foil 92 substrate and prevent the copper foil 92 from being torn.

[0021] It should be noted that the spot weld strength testing device described in this utility model is used for, but not limited to, spot weld testing. For ease of explanation, this utility model only uses the application of the spot weld strength testing device to spot weld testing as an example. The principle of the spot weld strength testing device applied to other types of equipment is essentially the same as that applied to spot weld testing, and will not be described in detail here.

[0022] Please see Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of a spot weld strength testing device provided in one embodiment of the present invention. Figure 2 This is a schematic diagram of a spot weld strength testing device provided in an embodiment of the present invention. The spot weld strength testing device includes a pressure plate 10, a fixing component 20, a driving structure 30, and a force measuring component 40, which aims to effectively protect the copper foil 92 substrate and prevent the copper foil 92 from being torn, while also ensuring the accuracy of the testing of the reliability of the spot weld between the copper foil 92 and the copper mesh 91 and the workpiece 90.

[0023] The pressure plate 10 is used to cover and flatten the workpiece 90 to be tested during the inspection process. The workpiece 90 is typically a composite structure of copper foil 92 and copper mesh 91 connected by spot welding. The copper foil 92 is thin and easily deformed. The pressure plate 10 provides planar support before tensile loading, keeping the copper foil 92 flat and avoiding stress concentration caused by warping or wrinkles. The pressure plate 10 has a through-hole 11 located at the corresponding position in the inspection area, which provides a channel for the tensile path, allowing the subsequent fastener 20 to pass through the hole and hook onto the copper mesh 91. The size of the through-hole 11 can be set according to the distribution of weld points and the specifications of the copper mesh 91, and is generally slightly larger than the size of the hook end of the fastener 20 to ensure smooth insertion and avoid interference.

[0024] The fixing member 20 passes through the clearance hole 11 of the pressure plate 10 and is used to hook and hang on the welding part or adjacent area of ​​the copper mesh 91 to achieve force transmission during the stretching process. The rear end of the fixing member 20 is connected to the drive structure 30, so that it can be driven to move along the preset stretching direction during the detection process. The drive structure 30 is used to provide stretching power, and in this embodiment, it can be a combination of a motor, a reduction mechanism, or a slide rail guide assembly. The output end of the drive structure 30 is fixedly connected to the rear end of the fixing member 20. The rotation of the motor drives the fixing member 20 to move along the set path, thereby generating an upward (or outward) tensile force on the copper mesh 91, so that the welding point is subjected to a gradually increasing tensile load. When the tensile force reaches the critical value of the welding point, the copper mesh 91 separates from the copper foil 92. The entire process can be set by the controller to set the stretching speed and displacement range to ensure smooth loading and accurate data. The force measuring member 40 is set at the connection part of the fixing member 20 or the drive structure 30 to detect the tensile force on the fixing member 20 in real time during the stretching process. This structural arrangement allows for real-time determination of the tensile strength of weld joints while ensuring detection accuracy, providing a reliable basis for assessing weld strength.

[0025] In this embodiment, the pressure plate 10 presses against the surface of the workpiece 90 outside the relief hole 11, forming a planar constraint and support for the entire copper foil 92. This disperses the concentrated local load to the surrounding area when external force is applied, effectively reducing the stress intensity of a single point on the copper foil 92 near the solder joint and preventing tearing, bulging, or warping caused by stress concentration in non-test areas. Simultaneously, the relief hole 11 on the pressure plate 10 defines the effective area of ​​the tensile force. The geometric boundary of the relief hole 11 defines a single, fixed force path in space, ensuring that the tensile force is transmitted to the solder joint only through the connection between the fixing member 20 and the copper mesh 91. This prevents other areas of the copper foil 92 from directly bearing axial tensile loads during testing, thus preventing non-test areas from being affected or deformed. Under this structural constraint, the force value detected by the force measuring member 40 accurately reflects the true bonding strength of the solder joint, ensuring the accuracy and repeatability of the tensile force sensing measurement.

[0026] In some embodiments, the cross-sectional area of ​​the relief hole 11 does not exceed 15% of the total area of ​​the copper mesh 91. By limiting the opening ratio of the relief hole 11, the pressure plate 10 can maintain sufficient support for the copper foil 92 while ensuring smooth force transmission.

[0027] When the area of ​​the relief hole 11 is too large, the effective support area of ​​the copper foil 92 within the detection area will be significantly reduced, making it prone to local suspension during stretching. This leads to stress concentration at the edge of the hole, increasing the risk of the copper foil 92 breaking or deforming. Conversely, when the area of ​​the relief hole 11 is controlled within 15% of the area of ​​the copper mesh 91, the pressure plate 10 can form a continuous force band around the relief hole 11, allowing the tensile load to be more evenly distributed on the surface of the copper foil 92. This ensures a smooth force path at the solder joint and avoids weakening the support performance of the substrate.

[0028] In some optimized embodiments, please refer to Figure 3 , Figure 3 This is a schematic diagram of the structure of a pressure plate 10 provided in an embodiment of this utility model. The spot weld strength testing device also includes a bushing 50, which is nested in the relief hole 11 of the pressure plate 10 and is used to adjust the effective diameter of the relief hole 11. The bushing 50 can be a replaceable or detachable structure, and its outer circumferential surface is interference-fitted or fitted with the inner wall of the relief hole 11 to achieve stable fixation. By setting the bushing 50 in the relief hole 11, the opening size of the relief hole 11 can be flexibly adjusted according to different specifications of copper mesh 91, weld point distribution, or hook end size of the fixing component 20 to meet the testing needs of various types of samples.

[0029] The inner diameter of the bushing 50 determines the movement space of the fastener 20 when it passes through, and its size can be controlled by replacing different models of bushing 50. For example, when inspecting a finer copper mesh 91 structure, a bushing 50 with a smaller inner diameter can be selected to reduce the effective aperture and improve the continuity of the support ring band; while when inspecting samples with larger aperture copper mesh 91 or special solder joint layouts, a bushing 50 with a larger aperture can be replaced to ensure that the fastener 20 can pass through smoothly and maintain a consistent force direction. Through this structural arrangement, the size of the clearance hole 11 can be quickly switched and adapted without changing the main body of the pressure plate 10, improving the versatility and modularity of the device.

[0030] Furthermore, in some embodiments, an elastic layer 60 is provided at the edge of the relief hole 11 or the bushing 50. The elastic layer 60 is used to adhere to the surface of the copper foil 92 during the testing process, thereby dispersing pressure and reducing stress concentration. The elastic layer 60 may be arranged in a ring shape at the inner edge of the relief hole 11 or the bushing 50, and its shape corresponds to the outline of the hole to form a continuous flexible contact interface. When the pressure plate 10 presses against the surface of the copper foil 92 and begins to apply tension, the elastic layer 60 can generate a small deformation at the contact point between the copper foil 92 and the hole, absorbing and balancing the local load, and preventing the edge of the copper foil 92 from being indented, scratched, or torn due to hard contact.

[0031] The material of the elastic layer 60 can be selected from materials with good resilience, such as silicone, polyurethane, rubber pads, or flexible foam, depending on the testing environment and accuracy requirements. Its thickness is generally set to 0.2mm to 1mm to maintain structural stability while ensuring cushioning. The elastic layer 60 can be fixed to the edge of the orifice by adhesive bonding, or it can be integrally formed with the bushing 50 or assembled by a snap-fit ​​structure, facilitating replacement and maintenance.

[0032] In one embodiment, the fastener 20 may take the form of a barbed structure, a mechanical gripper or a vacuum suction cup, etc., to meet the inspection requirements of different types of copper mesh 91 and solder joint structures.

[0033] When the fixing member 20 is a barb structure, its front end is provided with backward-sloping hook teeth or barbs, which can automatically hook onto the wire after passing through the mesh of the copper mesh 91. When the driving structure 30 applies tension, a reliable mechanical engagement is formed between the barb and the copper mesh 91, thereby preventing it from falling off during the stretching process. This structure is simple in design and suitable for copper mesh 91 samples with regular apertures and dense solder joints, enabling rapid hooking and stable force application.

[0034] When the fixing component 20 is a mechanical gripper structure, its front end includes one or more pairs of openable gripping claws. The grippers can be opened and closed by a micro motor, cylinder, or elastic mechanism. Before testing, the grippers open to grasp the edge or solder joint area of ​​the copper mesh 91, and then automatically close and lock before loading, achieving precise positioning of the test point. This gripping method can provide adjustable clamping force, suitable for multi-layer composite or irregularly edged copper mesh 91 structures, ensuring uniform force during loading and reducing slippage of the copper mesh 91.

[0035] In another embodiment, the fixture 20 can be a vacuum suction cup structure. The vacuum suction cup, connected to a vacuum pump or negative pressure generator, temporarily fixes itself to the surface of the copper mesh 91 before testing through suction force. Compared to mechanical clamping, vacuum suction avoids localized indentations or stress concentrations caused by mechanical contact, and is particularly suitable for thin copper mesh 91 structures with flat surfaces and small solder joint spacing. After testing, it automatically releases itself by simply releasing the negative pressure, offering advantages such as ease of operation and minimal damage to the sample.

[0036] In one embodiment, the edge of the pressure plate 10 is provided with a locking component 70, which is used to fix the position of the workpiece 90 during the testing process, thereby ensuring the stability and accuracy of the workpiece 90 throughout the tensile testing process. The locking component 70 can connect the workpiece 90 and the pressure plate 10 by mechanical or electrical means to prevent the workpiece 90 from shifting or deviating when tensile force is applied.

[0037] Optionally, the locking component 70 may include a locking buckle, a slot, or an adjusting bolt. The locking buckle can be disposed on the edge of the pressure plate 10 and automatically fastened by a spring or mechanical means to ensure the stable positioning of the workpiece 90 on the pressure plate 10. The slot structure achieves a locking connection between the workpiece 90 and the pressure plate 10 by engaging the edge or frame part of the workpiece 90, preventing displacement of the workpiece 90 during testing. The adjusting bolt can be rotated to adjust its contact pressure, so that the pressure plate 10 can more evenly fix the workpiece 90 when pressure is applied, effectively reducing measurement errors caused by insecure fixing. In addition, the locking component 70 should be adjustable to accommodate workpieces 90 of different sizes and shapes. By adjusting the setting method or position of the locking component 70, it is possible to adapt to copper mesh 91 and copper foil 92 samples of different specifications, ensuring that the fixed position of the workpiece 90 remains consistent during each test.

[0038] In this embodiment, by providing a locking component 70 at the edge of the pressure plate 10, the measurement error caused by the unstable position of the workpiece 90 during tensile testing is effectively solved. The locking component 70 prevents the workpiece 90 from shifting due to external interference or tensile force throughout the testing process, thereby improving the accuracy and consistency of the test data. Simultaneously, it simplifies the operation process, reduces errors introduced by manually positioning the workpiece 90, and further improves testing efficiency and reliability.

[0039] In some embodiments, the spot weld strength testing device further includes a bracket 80, which serves as the supporting base for the spot weld strength testing device and is fixed to one side of the pressure plate 10. The drive structure 30 is mounted on the bracket 80. The main function of the bracket 80 is to provide stable support for the drive structure 30 and other related components.

[0040] One side of the bracket 80 is fixedly connected to the surface of the pressure plate 10, preventing the pressure plate 10 from shifting or deforming during operation. The drive structure 30 is mounted on the bracket 80, typically secured by bolts, slots, or pre-drilled mounting holes in the bracket 80. Through the stable support of the bracket 80, the drive structure 30 can precisely transmit tension to the fixing member 20, thereby applying a controllable tensile force to the copper mesh 91 and copper foil 92 workpiece 90. The bracket 80 ensures that the drive structure 30 operates in a stable environment, preventing drive errors or movement deviations caused by unstable support.

[0041] In this embodiment, the introduction of the bracket 80 not only enhances the structural stability of the device, but also improves the accuracy of the drive system, enabling the spot weld strength testing device to provide more reliable test results when performing tensile tests.

[0042] In one embodiment, the drive structure 30 includes a guide 31 and a drive 32, wherein the guide 31 is fixed to the bracket 80, and the drive 32 drives the fixing member 20 to move along the guide 31, which is intended to ensure that the fixing member 20 can move accurately along the set path during the tensile testing process and apply a uniform tensile force to the workpiece 90 to be tested.

[0043] The function of the guide member 31 is to provide a stable and linear motion path for the drive member 32. The guide member 31 is typically fixed to the bracket 80 and connected to the bracket 80 by bolts, slots, or welding, ensuring that the guide member 31 does not shift or deform during tensile loading. The shape of the guide member 31 can be straight or curved, depending on the required motion trajectory. The surface of the guide member 31 can be smoothed or coated with a low-friction material to reduce the frictional resistance between the drive member 32 and the guide member 31, thereby ensuring smooth and efficient force transmission.

[0044] The drive component 32 works closely with the guide component 31, and its main function is to provide tension and drive the fixed component 20 to move along the path of the guide component 31. The drive component 32 can be a motor, pneumatic cylinder, hydraulic drive, or stepper motor, etc., depending on the requirements of the detection system. The drive component 32 transmits power to the fixed component 20 through a mechanical connection, ensuring that the fixed component 20 moves along the guide component 31 with precise speed and position. During implementation, the drive component 32 can precisely control the application of tension to the fixed component 20, ensuring that it moves in a predetermined direction, speed, and force during the stretching process.

[0045] In this embodiment, the cooperation between the guide 31 and the drive 32 effectively reduces the detection error that may be caused by instability or friction problems in the drive system, so that the entire spot weld firmness detection system has the characteristics of high precision and high stability, and is suitable for accurate detection of welding quality.

[0046] Furthermore, in one embodiment, the guide 31 extends perpendicularly to the plane of the copper foil 92, allowing the fixing member 20 to perform tensile testing along the surface of the copper foil 92 in the vertical direction. This avoids the problem in traditional equipment where the tension cannot be accurately applied due to interference from the position of the clamp or bracket 80. The vertical configuration of the guide 31 ensures that the fixing member 20 remains aligned with the plane of the copper foil 92 throughout the testing process, guaranteeing the accuracy and stability of the applied tension.

[0047] Furthermore, the design of the guide member 31, which is perpendicular to the plane of the copper foil 92, effectively reduces interference with the copper foil 92 or the copper mesh 91, ensuring that the device can operate efficiently within a limited space. During tensile testing, the guide member 31 provides a clear and stable movement path for the entire device, avoiding device displacement or instability caused by non-perpendicular movement.

[0048] In one embodiment, please refer to Figure 4 , Figure 4 This is a schematic diagram of the pressure plate 10 and support column 81 provided in this embodiment of the utility model. The bracket 80 includes at least one support column 81, which can extend and retract along the direction perpendicular to the copper foil 92. The extension and retraction of the support column 81 allows the bracket 80 to flexibly adjust its height or position according to different workpiece 90 sizes or inspection requirements.

[0049] The telescopic function of the support column 81 is achieved through an adjustment mechanism. Common adjustment methods include screw rotation, spring compression, and pneumatic adjustment. During implementation, the user can change the overall height or position of the device by adjusting the telescopic length of the support column 81, according to the height of the workpiece 90, the thickness of the copper foil 92, and the specific requirements of tensile testing.

[0050] When testing different workpieces 90, the operator does not need to replace the bracket 80 or perform complex disassembly and assembly. Simply adjusting the height of the support column 81 allows for quick adaptation to new workpiece types 90, improving work efficiency. The adjustment device for the support column 81 can be equipped with a limit device to ensure stability and safety after adjustment, preventing test failure or equipment damage due to height instability or misoperation.

[0051] The specific embodiments of this utility model described above do not constitute a limitation on the scope of protection of this utility model. Any other corresponding changes and modifications made based on the technical concept of this utility model should be included within the scope of protection of the claims of this utility model.

Claims

1. A spot weld strength testing device, characterized in that, include: A pressure plate is used to cover and flatten the copper foil and copper mesh spot-welded workpiece to be tested. The pressure plate has a through clearance hole. A fastener is used to pass through the clearance hole and hook the copper mesh; A driving structure, connected to the fixing member, is used to drive the fixing member to move so as to separate the copper mesh from the copper foil; and The force measuring component, connected to the fixing component, is used to detect tensile force.

2. The spot weld strength testing device according to claim 1, characterized in that, The cross-sectional area of ​​the clearance hole does not exceed 15 percent of the area of ​​the copper mesh.

3. The spot weld strength testing device according to claim 2, characterized in that, The spot weld strength testing device also includes a bushing, which is nested inside the relief hole and used to adjust the effective diameter of the relief hole.

4. The spot weld strength testing device according to claim 3, characterized in that, The clearance hole or the edge of the bushing is provided with an elastic layer.

5. The spot weld strength testing device according to any one of claims 1 to 4, characterized in that, The fastener is a barbed structure, a mechanical gripper, or a vacuum suction cup.

6. The spot weld strength testing device according to any one of claims 1 to 4, characterized in that, The edge of the pressure plate is provided with a locking component, which is used to fix the position of the workpiece.

7. The spot weld strength testing device according to any one of claims 1 to 4, characterized in that, The spot weld strength testing device also includes a bracket, which is fixed to one side of the pressure plate, and the drive structure is mounted on the bracket.

8. The spot weld strength testing device according to claim 7, characterized in that, The driving structure includes a guide and a driving member. The guide is fixed to the bracket, and the driving member drives the fixed member to move along the guide.

9. The spot weld strength testing device according to claim 8, characterized in that, The extension direction of the guide is perpendicular to the plane of the copper foil.

10. The spot weld strength testing device according to claim 7, characterized in that, The bracket includes at least one support column that is telescopic in a direction perpendicular to the copper foil.

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