High-speed cable welding spot pseudo soldering detection equipment and method

Abstract

The invention discloses a high-speed cable welding spot pseudo soldering detection device and method, and the device comprises a product fixing mechanism which is used for fixing a high-speed cable; the movement mechanism comprises an X-direction movement module and an oblique movement module mounted at the moving end of the X-direction movement module; according to the invention, the visual inspection mechanism is used for identifying the actual position of a welding spot and compensating a test point in real time, so that the positioning error caused by poor repeated precision of manual feeding and part tolerance is thoroughly eliminated, a test pen point can be accurately aligned with each welding spot, and the consistency and accuracy of detection are ensured from the source; the pressure sensor and the displacement sensor are adopted to synchronously collect data, judgment is performed by analyzing the slope of a pressure-displacement curve, the unique mechanical property mutation of the pseudo soldering point can be sensitively captured, the judgment basis is scientific and objective and is far superior to qualitative judgment manually based on hand feeling and experience, and the detection result is extremely reliable.

Description

Technical Field

[0001] This invention relates to the field of solder joint inspection technology, and in particular to a device and method for detecting poor solder joints in high-speed cables. Background Technology

[0002] High-speed cables are commonly used for transmitting high-speed data and are widely applied in fields such as big data analytics, cloud computing, and automobiles. The transmission quality and stability of high-speed cables largely depend on the welding quality of the cable solder joints. Currently, the main methods for solder joint inspection are non-contact and contact methods. Non-contact inspection is convenient and quick, but it is limited by the presence or absence of solder joints and cannot effectively detect the welding quality. The most common contact inspection method is manual side-pushing inspection, but this method is inefficient and prone to inconsistencies. Furthermore, due to the small area of ​​the solder joint at the connection point of a high-speed cable, there are microscopic positional differences, making manual contact inspection for the presence of cold solder joints difficult. To overcome the problem of detecting cold solder joints in high-speed cables, this invention proposes a device and method for detecting cold solder joints in high-speed cables. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides the following technical solution: A high-speed cable solder joint defect detection device includes: Product fixing mechanism, used to fix high-speed cables; The motion mechanism includes an X-axis motion module and an oblique motion module mounted on the moving end of the X-axis motion module; A data acquisition mechanism is installed on the moving end of the oblique motion module. The data acquisition mechanism includes a mechanical sensing unit for contacting the solder joint during the test and detecting the lateral force it is subjected to, a displacement sensing unit for detecting the displacement generated by the mechanical sensing unit under the lateral force, and an elastic element for providing initial preload pressure. A visual inspection mechanism is used to acquire images of solder joints and determine the actual position of the solder joints based on the images. The control system is electrically connected to the data acquisition mechanism and the vision inspection mechanism. The control system is configured to: control the motion mechanism to position the data acquisition mechanism to the target weld point based on the actual position of the weld point obtained by the vision inspection mechanism; control the oblique motion module to drive the data acquisition mechanism to perform a side push test on the weld point; and simultaneously acquire force data from the mechanical sensing unit and displacement data from the displacement sensing unit; and analyze the mechanical characteristics of the weld point and determine whether there is a cold weld based on the force data and displacement data.

[0004] As an improvement to the above technical solution, the product fixing mechanism includes: The carrier has a cavity on which the solder joint end of the high-speed cable is placed; A clamping assembly for clamping and fixing the weld point detection end placed in the cavity; Clamping cylinder assembly, used to limit and fix the carrier; A cable storage pit, located next to the carrier, is used to organize high-speed cables.

[0005] As an improvement to the above technical solution, the mechanical sensing unit includes a pressure sensor and a test pen tip. The pressure sensor is fixedly connected to the test pen tip. The displacement sensing unit is a displacement sensor, and its measuring end is in contact with the pressure sensor to measure the deformation of the elastic element.

[0006] As an improvement to the above technical solution, the data acquisition mechanism further includes an L-shaped fixing member and a limiting block. The L-shaped fixing member is fixedly connected to the moving end of the inclined motion module. The pressure sensor is fixedly connected to the limiting block by bolts. The limiting block and the L-shaped fixing member are limited to their initial relative positions by an elastic element, so that the elastic element has an initial compression amount to provide the initial pre-tightening pressure.

[0007] As an improvement to the above technical solution, the visual inspection mechanism includes a camera mounting plate disposed on the X-axis motion module, a camera mounted on the camera mounting plate, a downward-facing lens mounted on the camera, a ring light source mounting plate fixedly disposed on the camera mounting plate and located below the lens, and a light source fixedly disposed on the light source mounting plate.

[0008] As an improvement to the above technical solution, a marking mechanism is also included. The marking mechanism includes a sliding cylinder fixed to the front end of the L-shaped fastener by bolts, a fixing block disposed below the sliding cylinder and fixedly connected to the output end of the sliding cylinder, and a marker pen interference-fitted into the fixing block. The sliding cylinder is electrically connected to the control system and is used to mark unqualified products according to the result of the cold solder joint judgment.

[0009] As an improvement to the above technical solution, the base, product fixing mechanism and X-axis motion module are all fixedly mounted on the base, and a dual-control start button is installed on the side wall of the base.

[0010] The method for detecting poor weld joints in high-speed cables includes the following steps: S1: Secure the high-speed cable to the product fixing mechanism; S2: Obtain an image of at least one solder joint through the vision inspection mechanism, identify its actual position, calculate the error between the actual position and the theoretical position, and compensate for this error to the theoretical test position of the solder joint to obtain the actual test position; S3: Control the motion mechanism to move the data acquisition mechanism to the actual test position, and then control the oblique motion module to drive the data acquisition mechanism to perform a side push test on the solder joint, and synchronously collect force value data and displacement data; S4: Generate a pressure-displacement curve based on the collected force value data and displacement data, calculate the slope E of the curve. When E ≥ k, it is determined that the solder joint is qualified; when E < k, it is determined that the solder joint has a virtual welding defect, where k is a preset threshold.

[0011] Advantages of the present invention: By using the vision detection mechanism to identify the actual position of the solder joint and perform real-time compensation on the test points, the positioning error caused by the poor repeatability accuracy of manual feeding and part tolerances is completely eliminated, ensuring that the test pen tip can accurately align with each solder joint, and guaranteeing the consistency and accuracy of detection from the source; By using a pressure sensor and a displacement sensor to synchronously collect data and judging by analyzing the slope of the pressure-displacement curve, the mechanical property mutation unique to virtual solder joints can be sensitively captured. The judgment basis is scientific and objective, far superior to the qualitative judgment by manual feeling and experience, and the detection result is extremely reliable. Description of the Drawings

[0012] Figure 1 It is a schematic structural diagram of the present invention; Figure 2 It is a schematic structural diagram of the vision detection mechanism of the present invention; Figure 3 It is a schematic structural diagram of the data acquisition structure and the scribing mechanism of the present invention; Figure 4 It is a schematic structural diagram of the motion mechanism of the present invention; Figure 5 It is a schematic structural diagram of the product fixing mechanism of the present invention; Figure 6 is Figure 5 The enlarged structural diagram at position A in

[0013] Reference numerals: 1, dual-control start button; 2, vision detection mechanism; 21, camera fixing plate; 22, camera; 23, lens; 24, light source fixing plate; 25, light source; 3, X-direction motion module; 4, oblique motion module; 5, data acquisition mechanism; 51, L-shaped fixing piece; 52, displacement sensor; 53, elastic element; 54, pressure sensor; 55, test pen tip; 56, limit block; 6, base; 7, product fixing mechanism; 71, right clamping cylinder; 72, right clamp; 73, carrier; 74, left clamp; 75, left clamping cylinder; 76, cable storage cavity; 77, support frame; 8, placement mechanism; 9, scribing mechanism; 91, sliding cylinder; 92, fixing block; 93, marker pen. Detailed Embodiment

[0014] To make the objectives, technical solutions, and advantages of this invention clearer, the invention 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 and not intended to limit the invention.

[0015] Example 1 A high-speed cable weld joint cold solder joint detection device includes: a base 6, a product fixing mechanism 7, a motion mechanism, a data acquisition mechanism 5, a vision inspection mechanism 2, a placement mechanism 8, and a control system; the product fixing mechanism 7 and the X-axis motion module are both fixedly mounted on the base 6, and a dual-control start button 1 is installed on the side wall of the base 6; Product fixing mechanism 7 includes: Support frame 77 is fixed on base 6; The carrier 73 is fixed on the top of the support frame 77, and a cavity is provided on it for placing the solder joint end of the high-speed cable. A clamping assembly for clamping and fixing the weld point detection end placed in the cavity; Clamping cylinder assembly, used to limit and fix the carrier 73; Cable storage pit 76 is located next to the carrier 73 and is used to organize the cables of high-speed cables; The clamping assembly includes a right clamp 72 and a left clamp 74, and the clamping cylinder assembly includes a right clamping cylinder 71 and a left clamping cylinder 75. refer to Figure 5 as well as Figure 6 One solder joint end of the high-speed cable is placed into the left clamp 74 and locked in place by the buckle on it. The entire cable is then placed into the left cavity of the carrier 73. Subsequently, the other solder joint end of the high-speed cable is placed into the right clamp 72 and locked in place. The entire cable is then placed into the right cavity of the carrier 73. After the equipment is started, the right clamping cylinder 71 and the left clamping cylinder 75 extend to limit and fix the left clamp 74 and the right clamp 72 in the cavity, thereby firmly pressing the high-speed cable onto the carrier 73 and completing the fixation before testing. refer to Figure 4 The motion mechanism includes an X-axis motion module 3 and an oblique motion module 4 mounted on the moving end of the X-axis motion module 3. refer to Figure 2The visual inspection mechanism 2 is used to acquire solder joint images and obtain the actual position of the solder joint based on the images; the visual inspection mechanism 2 includes a camera mounting plate 21 set on the X-axis motion module 3, a camera 22 mounted on the camera mounting plate 21, a downward-facing lens 23 mounted on the camera 22, a ring light source mounting plate 24 fixedly set on the camera mounting plate 21 and located below the lens 23, and a light source 25 fixedly set on the light source mounting plate 24; When the X-axis motion module 3 carries the entire vision inspection mechanism 2 to move above the preset teaching and photographing point via the camera fixing plate 21, the control system will trigger an image acquisition command. The light source 25 can provide uniform and shadowless illumination to the solder joint below. Under optimized lighting conditions, the camera 22 captures a clear and high-contrast image of the solder joint through its downward-facing lens 23. The theoretical position of the solder joint obtained through the teaching and photographing point is used to obtain the position of the high-speed cable solder joint through image processing, calculate the error between the theoretical position and the position, and compensate for it to the corresponding test position. refer to Figure 3 The data acquisition mechanism 5 is installed on the moving end of the oblique motion module 4. The data acquisition mechanism 5 includes a mechanical sensing unit for contacting the solder joint during the test and detecting the lateral force it is subjected to, a displacement sensing unit for detecting the displacement generated by the mechanical sensing unit under the lateral force, and an elastic element 53 for providing initial preload pressure. The mechanical sensing unit includes a pressure sensor 54 and a test pen tip 55. The pressure sensor 54 is fixedly connected to the test pen tip 55. The displacement sensing unit is a displacement sensor 52, whose measuring end is in contact with the pressure sensor 54, and is used to measure the deformation of the elastic element 53. The data acquisition mechanism 5 also includes an L-shaped fixing member 51 and a limiting block 56. The L-shaped fixing member 51 is fixedly connected to the moving end of the inclined motion module 4. The pressure sensor 54 is fixedly connected to the limiting block 56 by bolts. The limiting block 56 and the L-shaped fixing member 51 are limited to an initial relative position by an elastic element 53, so that the elastic element 53 has an initial compression amount to provide the initial pre-tightening pressure. Specifically, in the non-working state, the elastic element 53 stores elastic potential energy due to pre-compression between the limiting block 56 and the L-shaped fixing member 51, thus providing a stable initial pre-tightening pressure for the entire measurement system. When working, the X-axis motion module 3 drives the test pen tip 55 to the compensated test position via the oblique motion module 4. When the oblique motion module 4 drives the data acquisition mechanism 5 to slowly advance towards the solder joint, the test pen tip 55 first contacts the solder joint. Subsequently, the oblique motion module 4 continues to advance, and this advancing force is transmitted through the L-shaped fixing member 51 and the elastic element 53, ultimately manifesting as a lateral force acting on the solder joint. This force is generated by the test pen tip 55... The pressure sensor 54, which is rigidly connected to the tip 55, directly and in real time detects and converts the pressure into an electrical signal (force data F). At the same time, due to the reaction force generated by the solder joint on the test tip 55, this reaction force will attempt to further compress the elastic element 53. The deformation of the elastic element 53 (i.e., the change in compression) causes a relative displacement between the pressure sensor 54 and the L-shaped fixing member 51. This relative displacement is captured in real time by the displacement sensor 52 and converted into an electrical signal (displacement data X). The data acquisition card will collect the data from the pressure sensor 54 and the displacement sensor 52. After the test is completed, the process will be repeated for other solder joint tests. The elastic element 53 is a spring. The control system is electrically connected to the data acquisition mechanism 5 and the vision inspection mechanism 2. The control system is configured to: control the motion mechanism to position the data acquisition mechanism 5 to the target weld point according to the actual position of the weld point obtained by the vision inspection mechanism 2; control the oblique motion module 4 to drive the data acquisition mechanism 5 to perform a side push test on the weld point; and simultaneously acquire force data from the mechanical sensing unit and displacement data from the displacement sensing unit; and analyze the mechanical characteristics of the weld point and determine whether there is a cold weld based on the force data and displacement data. Specifically, the control system will draw the collected data into a visual pressure-time curve, displacement-time curve, and pressure-displacement curve. While drawing the curves, the control system will analyze the peaks and valleys, slopes, and other data of the curves. After comparing and analyzing these data with preset thresholds, the detection results will be obtained. Among them, the basis for judging the cold solder joint can be divided into three parts, namely the pressure-time curve, displacement-time curve, and pressure-displacement curve. In the pressure-time curve, when the maximum pressure point F is within the set value range [F0, F1], it indicates that the pressure test is normal. In the displacement-time curve, when the maximum displacement X is within the set value range [X0, X1], it indicates that the displacement test is normal. In the pressure-displacement curve graph, the slope dF / dX of the test curve is denoted as E. Assume there is a threshold k (k > 0). When E ≥ k, it indicates that there is no false soldering in the tested solder joint, that is, it is a qualified solder joint, where k is related to the elastic modulus of the spring; when E < k, it indicates that there is false soldering in the tested solder joint. At this time, there will be a mutation point in the pressure-displacement curve, that is, the displacement remains unchanged and the pressure will decrease sharply. When the curve stabilizes, finally E will become k. Similarly, during the test process, there will also be turning points in the pressure-time curve and the displacement-time curve, and then it will maintain stability. Moreover, the values measured for the false solder joints are all smaller than the set interval of pressure and displacement. It further includes a scribing mechanism 9. The scribing mechanism 9 includes a sliding cylinder 91 fixedly connected to the front end of the L-shaped fixing member 51 by bolts, a fixing block 92 disposed below the sliding cylinder 91 and fixedly connected to the output end of the sliding cylinder 91, and a marking pen 93 press-fitted into the fixing block 92. The sliding cylinder 91 is electrically connected to the control system and is used to mark unqualified products according to the false soldering judgment result. Specifically, when the device is performing detection, the scribing mechanism is in a standby state. The sliding cylinder 91 is in a contracted position, driving the fixing block 92 and the marking pen 93 fixed thereto to be in a lifted state. At this time, the tip of the marking pen is far from the high-speed cable below, ensuring that it will not interfere with the normal detection process and product safety. When the control system analyzes and determines that there is false soldering in the current high-speed cable (i.e., it is a defective product) based on the force and displacement data fed back by the data acquisition mechanism 5, the control system will immediately send a driving signal to the sliding cylinder 91 of the scribing mechanism 9. After receiving the signal, the piston rod of the sliding cylinder 91 quickly extends, pushing the fixing block 92 below it and the marking pen 93 press-fitted on the fixing block to move downward as a whole. Under the drive of the sliding cylinder 91, the tip of the marking pen 93 contacts the insulating outer skin of the high-speed cable or a specific marking area of the connector with a certain pressure, and under the coordinated drive of the X-direction movement module 3, a clear mark is drawn. This mark clearly identifies this product as a "defective product". After completing the scribing action, the piston rod of the sliding cylinder 91 automatically retracts, driving the marking pen 93 to lift and returning to the standby state again to prepare for the next detection cycle.

[0016] A placement mechanism 8 is disposed below the base 1. The placement mechanism 8 can place items such as a mouse and a keyboard.

[0017] Set the product photo-taking points: Refer to Figure 1 And Figure 2 , it is necessary to move the vision acquisition mechanism 2 so that the solder joint in the acupuncture point is at the center of the field of view of the camera 22, and record these two positions in the upper computer as the points for the first and second photo-taking.

[0018] Set up product test points: See Figure 1 and Figure 5 Different high-speed cable products have different solder joint positions, numbers, and spacings. It is necessary to record the positions of the solder joints in the acupoints on the left and right sides of the carrier 73, manually control the X-axis motion module 3 and the oblique motion module 4, so that the test pen tip 55 is aligned with the first solder joint to be tested in the acupoint on the left side of the carrier 73, record this point in the control system as the test starting point, and record the theoretical feed distance of the test pen tip 55 according to the process specifications. The theoretical test positions of other solder joints will be calculated in real time based on the solder joint spacing and the spacing of the acupoints on the left and right sides.

[0019] Set product marking points: See Figure 1 and Figure 5 Manually control the X-axis motion module 3 and the diagonal motion module 4 to find the optimal starting and ending points for drawing lines, and record these two positions in the control system as the drawing points.

[0020] This invention self-test Before each production test, the high-speed cable weld joint cold solder joint detection equipment needs to be self-tested to determine whether the equipment's photo-taking and data acquisition functions are normal. The specific process is as follows: Place the weld points on both sides of the inspection sample into the right clamp 72 and the left clamp 74 respectively, and after fixing them, place them into the carrier 73. Turn on the control system, initialize the equipment to zero, select the corresponding inspection program, and press the dual-control start button 1. The X-axis motion module 3, carrying the camera 22, moves to the set position, takes pictures, processes them, and outputs the error value for the position correction of the test point. Then, it moves to each weld point in sequence and starts testing. Analyze the data curve collected from each weld point to determine its weld quality. If it is consistent with the manual test data, the test function is normal; otherwise, the test function is abnormal and the equipment function needs to be checked again.

[0021] Automatic testing of this invention Automatic testing can only be switched to after the equipment functions normally. Otherwise, automatic testing cannot be performed. The specific process of automatic testing is as follows: After the weld point to be tested is clamped by the right clamp 72 and the left clamp 74, it is placed into the two cavities of the carrier 73. The corresponding test program is manually selected, and the double-control start button 1 is pressed. The motion mechanism will take pictures of the set photo position and compensate the results to the theoretical test point to obtain the actual test point. Then, based on the actual test point, each weld point is tested and data is collected. It is determined whether the collected test data meets the set range. If it meets the set range, it is judged as a qualified product and flows into the next process. If it is judged as a defective product, the marking mechanism will mark it and it will flow into the defective area.

[0022] Embodiment 2 A method for detecting false soldering of solder joints of a high-speed cable, comprising the following steps: S1: Fix the high-speed cable on the product fixing mechanism 7; S2: Obtain images of at least one solder joint through the vision detection mechanism 2, identify its actual position, calculate the error from the theoretical position, and compensate this error to the theoretical test position of the solder joint to obtain the actual test position; S3: Control the motion mechanism to move the data acquisition mechanism 5 to the actual test position, and then control the oblique motion module 4 to drive the data acquisition mechanism 5 to perform a side push test on the solder joint, and synchronously collect force value data and displacement data; S4: Generate a pressure-displacement curve based on the collected force value data and displacement data, calculate the slope E of this curve. When E≥k, it is determined that the solder joint is qualified; when E<k, it is determined that there is false soldering at the solder joint, where k is a preset threshold.

[0023] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it.

Claims

1. A high-speed cable solder joint defect detection device, characterized in that, include: Product fixing mechanism, used to fix high-speed cables; The motion mechanism includes an X-axis motion module and an oblique motion module mounted on the moving end of the X-axis motion module; A data acquisition mechanism is installed on the moving end of the oblique motion module. The data acquisition mechanism includes a mechanical sensing unit for contacting the solder joint during the test and detecting the lateral force it is subjected to, a displacement sensing unit for detecting the displacement generated by the mechanical sensing unit under the lateral force, and an elastic element for providing initial preload pressure. A visual inspection mechanism is used to acquire images of solder joints and determine the actual position of the solder joints based on the images. The control system is electrically connected to the data acquisition mechanism and the vision inspection mechanism. The control system is configured to: control the motion mechanism to position the data acquisition mechanism to the target weld point based on the actual position of the weld point obtained by the vision inspection mechanism; control the oblique motion module to drive the data acquisition mechanism to perform a side push test on the weld point; and simultaneously acquire force data from the mechanical sensing unit and displacement data from the displacement sensing unit; and analyze the mechanical characteristics of the weld point and determine whether there is a cold weld based on the force data and displacement data.

2. The high-speed cable weld joint defect detection equipment according to claim 1, characterized in that: The product fixing mechanism includes: The carrier has a cavity on which the solder joint end of the high-speed cable is placed; A clamping assembly for clamping and fixing the weld point detection end placed in the cavity; Clamping cylinder assembly, used to limit and fix the carrier; A cable storage pit, located next to the carrier, is used to organize high-speed cables.

3. The high-speed cable weld joint defect detection equipment according to claim 1, characterized in that: The mechanical sensing unit includes a pressure sensor and a test pen tip. The pressure sensor is fixedly connected to the test pen tip. The displacement sensing unit is a displacement sensor, and its measuring end is in contact with the pressure sensor to measure the deformation of the elastic element.

4. The high-speed cable weld joint defect detection equipment according to claim 3, characterized in that, The data acquisition mechanism further includes an L-shaped fixing member and a limiting block. The L-shaped fixing member is fixedly connected to the moving end of the inclined motion module. The pressure sensor is fixedly connected to the limiting block by bolts. The limiting block and the L-shaped fixing member are limited to their initial relative positions by an elastic element, so that the elastic element has an initial compression amount to provide the initial pre-tightening pressure.

5. The high-speed cable weld joint defect detection equipment according to claim 4, characterized in that: The visual inspection mechanism includes a camera mounting plate disposed on the X-axis motion module, a camera mounted on the camera mounting plate, a downward-facing lens mounted on the camera, a ring light source mounting plate fixedly disposed on the camera mounting plate and located below the lens, and a light source fixedly disposed on the light source mounting plate.

6. The high-speed cable weld joint defect detection equipment according to claim 4, characterized in that: It also includes a marking mechanism, which includes a sliding cylinder fixed to the front end of the L-shaped fastener by bolts, a fixing block located below the sliding cylinder and fixedly connected to the output end of the sliding cylinder, and a marker pen that is interference-fitted into the fixing block. The sliding cylinder is electrically connected to the control system and is used to mark unqualified products based on the result of the cold solder joint judgment.

7. The high-speed cable weld joint defect detection equipment according to claim 1, characterized in that: It also includes a base, a product fixing mechanism, and an X-axis motion module, all of which are fixedly mounted on the base. A dual-control start button is installed on the side wall of the base.

8. A method for detecting cold welds at high-speed cable joints, applied to the high-speed cable cold weld detection equipment according to any one of claims 1-7, characterized in that, Includes the following steps: S1: Secure the high-speed cable to the product fixing mechanism; S2: Obtain an image of at least one solder joint through the vision inspection mechanism, identify its actual position, calculate the error between the actual position and the theoretical position, and compensate for this error to the theoretical test position of the solder joint to obtain the actual test position; S3: Control the motion mechanism to move the data acquisition mechanism to the actual test position, and then control the oblique motion module to drive the data acquisition mechanism to perform a side push test on the weld point, and simultaneously collect force data and displacement data; S4: Generate a pressure-displacement curve based on the collected force and displacement data, and calculate the slope E of the curve. When E ≥ k, the weld is deemed qualified; when E < k, the weld is deemed to have a false weld, where k is a preset threshold.

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