PCB Technical - Inspection method and automation of PCB soldering

PCB fusion welding is a method in which the interface of the workpiece is heated to a molten state during the welding process and the welding is completed without pressure. During the welding process, the heat source rapidly heats and melts the joints of the two workpieces to be welded, forming a molten pool.

Common circuit boards in life

During the welding process, if the atmosphere is in direct contact with the high-temperature molten pool, the oxygen in the atmosphere will oxidize metals and various alloying elements. Nitrogen and water vapor in the atmosphere will enter the molten pool, and in the subsequent cooling process will also form holes, slag inclusions, cracks and other defects in the weld, which will reduce the quality and performance of the weld.

What are the welding tools for the circuit board? Currently, soldering technology of electronic components is mainly used. PCB soldering technology uses tin-based tin alloy material as solder, and the solder melts at a certain temperature, and the metal solder and tin atoms attract each other, diffuse and bond together, thereby forming a wet bonding layer. It appears that the copper platinum and component leads of the printed circuit board are very smooth. In fact, there are many tiny bumps on their surface. The molten tin solder diffuses along the solder surface through capillary suction, thereby forming solder and solder. The penetration of parts, components and printed boards is firmly combined and has good electrical conductivity.

The selective soldering process includes: flux spraying, circuit board preheating, dip soldering and drag soldering. Flux coating process In selective soldering, the flux coating process plays an important role. When the circuit board welding heating and soldering are to be completed, the flux should be very flexible to prevent bridging and prevent oxidation of the circuit board. The robot sprays the flux, passes the circuit board through the flux nozzle, and then sprays the flux to the soldering position of the PCB circuit board.

The inspection methods of PCB soldering quality include visual inspection, infrared inspection and online testing. Among these methods, the most economical and most commonly used is the visual method, which is economical, convenient, simple and feasible.

Automated PCB proofing

In the system that describes the behavior of the control process, the data structure of the stored process management and control information is called PCB proofing, which is a part of the process object and the most important record data of the operating system. For process management and control, the most important data structure is that each process has a PCB proofing process, and the entire process is run when the process is generated, until the PCB is generated and the process is cancelled. The PCB proofing records all the information required by the operating system to describe the current state of the process, which is the control process behavior of PCB proofing.

PCB proofed products

As a basic unit, PCB proofing can independently execute programs that cannot be executed independently in multiple program environments, including data, of course. PCB proofing is a process that can be executed simultaneously with other processes. This is a process based on PCB proofing, or a process that controls and manages concurrent running. The PCB proofing is a static description of the process, which consists of three parts: PCB, associated program segments, and a data structure set in which the program segments are run. The function of PCB proofing is to create a basic unit that can independently execute programs that cannot be executed independently in multiple program environments, and to create a process that can be executed simultaneously with other processes. Is to be done. The program segment is the program code segment that can be executed by the CPU by the process scheduler of the process, and the data segment of the process is the original data processed by the program corresponding to the process, or the intermediate or final value generated after the program is executed. Some of this may also be data, which is inaccurate.

Throughout the life cycle of the process, the system always uses PCB proofing to control the process. In other words, PCB proofing is being processed because the system is based on the PCB of the process and knows the existence of the process, instead of just displaying other things. This is undoubtedly a very good choice for our PCB proofing. The correctness of the process makes the stability and accuracy of PCB proofing, which is why so many automation manufacturers choose PCB proofing