PCB Tech - The solution to the PCBA throwing problem

PCBA processing is an indispensable step in the design and production process of electronic equipment. The PCB circuit board carries the control system of the electronic equipment. Its quality directly affects the operation of electronic equipment and product quality. A good product cannot be separated from high quality. PCBA processing, PCB circuit board support, and in the process of PCBA processing, it is inevitable that some problems will be encountered.

Today, I will explain to you one of the PCBA processing solutions: the reason for throwing materials and the solution 1: the nozzle problem, such as the nozzle deformation, blockage, damage caused by insufficient air pressure, air leakage, and the material cannot be sucked. If the material is incorrect, the identification fails and the PCBA throws the material.

Countermeasure: Clean and replace the nozzle;

Reason 2: The feeder problem, the feeder is set up incorrectly, the position is deformed, and the feeding mechanism is not good.

Countermeasures: reset the feeder, clean up the equipment, calibrate or replace the feeder.

Reason 3: Recognition system problems, poor vision, dirty vision or laser lens, foreign objects interfering with recognition, improper selection of recognition light source or insufficient intensity or grayscale, or the recognition system is broken.

Countermeasures: Clean and wipe the surface of the identification system, keep it clean and free of foreign matter, oil interference, etc., adjust the light source intensity and gray level, and replace the identification system components; Reason 4: Position problems, position shifts, and the suction nozzle is not in the center of the material when picking up the material. Incorrect reclaiming height (generally press down 0.05mm after touching the part) causes deviation, reclaiming is not correct, there is deviation, and the recognition does not match the corresponding data parameters and is discarded as invalid by the recognition system.

Countermeasures: adjust the reclaiming position, height and other parameters;

Reason 5: Vacuum problem, insufficient air pressure, unsmooth vacuum pipe passage, foreign matter blocking the vacuum pipe, or vacuum leakage caused insufficient air pressure and the material cannot be retrieved, or it falls on the way after picking it up.

Countermeasures: Adjust the air pressure steep slope to the required air pressure value of the equipment (generally 0.5~~0.6Mpa for the placement machine), clean and dredge the air pressure pipeline, repair the leaking air path; reason 6: the placement machine program problem, the component parameters in the edited program Wrong setting, inconsistent with the actual size, brightness and other parameters of the incoming material, which will cause the recognition to fail and be discarded.

Countermeasures: modify the component parameters, search for the best parameter value of the component;

Reason 7: incoming material problems, incoming materials are not standardized, or unqualified products such as oxidation of incoming pins.

Countermeasures: IQC will do a good job of incoming material inspection and contact the component supplier; Reason 8: Feeder problem, feeder deformation, feeder poor feeding (feeder ratchet gear is damaged, the material belt hole is not stuck in the feeding On the ratchet gear of the feeder, there are foreign objects under the feeder, the spring is aging, the strength is insufficient, or the electrical failure), resulting in insufficient or poor reclaiming, PCBA throwing, and damage to the feeder.

Countermeasures: correct the feeder, clean the feeder platform, replace the broken parts or the feeder; according to relevant research, static electricity is also a cause of PCBA throwing, so the placement machine should be grounded and the production site should be properly grounded. Anti-static work.

It is normal for the placement machine to have PCBA throwing away, but if the PCBA throwing rate is high, it will seriously affect the production efficiency and production cost, and it must be solved. When there is a serious PCBA throwing phenomenon, you can first ask the on-site personnel, through the description, and then based on the above seven reasons, observe and analyze directly to find the problem, so as to find out the cause more effectively, solve it, and improve production efficiency., But it takes up too much machine production time.