Introduction to the Issue of Material Throwing in Pick-and-Place Machines

One of the common issues during the pick-and-place process of a pick-and-place machine is component rejection.The normal working process of a pick-and-place machine involves the pick-up of surface-mount components from the feeder by the suction nozzles on the placement head. Subsequently, the optical system of the placement head scans or photographs the surface-mount components. The computer then compares the information of the surface-mount components with the information in the component library. If the information matches, the placement head uses the suction nozzles to blow the surface-mount components onto the specified positions of the PCB (Printed Circuit Board) that has been coated with solder paste. If an error occurs during the information comparison process, the placement head will blow the surface-mount components into the scrap bin instead of onto the PCB, causing the pick-and-place machine to sound an alarm and stop.

Component rejection leads to the removal of the surface-mount component from the packaging, and since the feeder is designed for continuous supply, the removed component cannot be recovered. Therefore, component rejection results in both wastage of surface-mount components and a significant reduction in production efficiency.

The causes of component rejection include issues related to the suction nozzles, optical system, pick-up position, insufficient vacuum, component library, and the components themselves.