In recent years, the production of automotive electronic ECU modules in industrial settings has faced two major challenges in the development and manufacturing of their main connectors:
First, the pin height measurement accuracy on the soldered surface of the product's PCB board is critical. Because pins are prone to deformation after bending, and external forces during assembly can also cause changes in pin height, it is essential to rigorously inspect the pin height before packaging to ensure accuracy and reliability for customers during use.
Secondly, due to the large number of pins in the product—reaching the pin count at the highest level in the connector industry—and the high unit price, it is essential to ensure 100% quality and reliability of all terminals. Therefore, all dimensions of the product's adapter and PCB terminals must be within the design specifications, necessitating multi-camera testing.
In machine vision applications, automated inspection machines mainly consist of five modules: 1) product cleaning and loading; 2) electrical testing module; 3) height and position detection module; 4) QR code marking and detection; and 5) robotic arm unloading and packaging.
The main inspection contents include: 1) the height of the product pins relative to the plastic; 2) the positional dimensions of the product pins inside the plastic and HSG deformation; 3) whether the entire HSG outer contour is deformed; 4) the height and missing product positioning posts.
The process is as follows:
1) After the pin bending is completed, the product is transferred to the cleaning module for cleaning to ensure that there are no HSG debris or other foreign objects in the product caused during the production process.
2) After cleaning, the product comes to the electrical testing module through the feeding mechanism. The main tests are to check whether there are any missing pins during the pin insertion process and whether there are any abnormal angles during bending, including product OS and Hipot tests.
3) After passing through the electrical testing module, the pin height is measured at the product Mate adapter. Since the terminals are hidden inside the HSG, they need to be transferred to the outside through the mechanism probe to measure the height of each terminal relative to the HSG. The Cognex In-Sight 5605 camera can quickly and stably establish the testing program.
4) After the pin height detection is completed, the machine proceeds to the PCB height measurement station. This is the most challenging part of the entire testing equipment and also the one with the longest evaluation time during the initial development process. Since the PCB pins are used to solder ECU modules, 100% accuracy and high quality must be guaranteed. However, the pins are not rigid enough to allow for the use of mechanical probes for measurement; only a non-contact measurement system can be used. Simultaneously, high precision, excellent repeatability, and reproducibility must be ensured, and the system must withstand MSA verification.
5) After the PCB height inspection is completed, the next workstation will inspect the terminal position and dimensions of the PCB end of the product. Then, the product will be inspected for OK or NG. After that, QR code marking and code verification will be performed. Finally, the product will be packaged by a robotic arm.
The above testing measures greatly ensure the high quality and stability of the products, while also reducing manpower and eliminating the omissions and uncertainties caused by human testing. This significantly improves the satisfaction and safety of the company's production testing.
