In the SMT production process, it is difficult to avoid the problem of throwing materials from the placement machine. Let’s take a look at the main reasons for SMT placement machine throwing.
The so-called throwing means that during the production process of the SMT placement machine, the material is not attached after it is sucked, but the material is thrown into the throwing box or other places, or the above throwing action is performed without the material being sucked. Throwing causes material loss, prolongs production time, reduces production efficiency, and raises production costs. In order to optimize production efficiency and reduce costs, it is necessary to solve the problem of high throwing rate.
The main reasons and countermeasures of throwing materials:
Reason 1: The nozzle problem, the nozzle is deformed, clogged, or damaged, resulting in insufficient air pressure and air leakage, causing the material to be sucked, incorrectly reclaimed, and the recognition fails and the material is thrown.
Countermeasure: Clean and replace the suction nozzle.
Reason 2: Recognition system problem, poor vision, unclean vision or laser lens, debris interfering with recognition, improper selection of recognition light source and insufficient intensity and grayscale, and the recognition system may be broken.
Countermeasures: Clean and wipe the surface of the identification system, keep it clean and free of debris, etc., adjust the intensity and gray level of the light source, and replace the identification system components.
Reason 3: Position problem, the reclaiming material is not in the center of the material, the reclaiming height is not correct (generally press 0.05MM after touching the part), which causes the deviation, the reclaiming is not correct, there is an offset, and the recognition is followed. The data parameters do not match and are discarded as invalid materials by the recognition system.
Countermeasure: Adjust the reclaiming position.
Reason 4: Vacuum problem, insufficient air pressure, unsmooth passage of the vacuum tube, a guide material blocking the vacuum passage, or vacuum leaks causing insufficient air pressure and the material cannot be retrieved, or it falls on the way after picking it up.
Countermeasures: Adjust the air pressure steeply to the required air pressure value of the equipment (such as 0.5~~0.6Mpa–YAMAHA placement machine), clean the air pressure pipeline, and repair the leaking air path.
Reason 5: Program problem. The component parameters in the edited program are not set correctly, and the parameters such as the actual size and brightness of the material do not match, which causes the recognition to fail and is discarded.
Countermeasures: Modify the component parameters and search for the best parameter settings for the component.
Reason 6: Incoming material problems, irregular incoming materials, unqualified products such as pin oxidation.
Countermeasures: IQC will do a good job inspection of incoming materials and contact the component supplier.
Reason 7: Feeder problem, feeder position deformation, feeder feeding failure (feeder ratchet gear is damaged, the material belt hole is not stuck on the feeder ratchet gear, there are foreign objects under the feeder, spring Aging, or electrical failure), resulting in material throwing due to insufficient or poor reclaiming, and damage to the feeder.
Countermeasures: adjust the feeder, clean the feeder platform, and replace damaged parts or feeders.