Function and principle of SPI solder paste inspection machine

SPI Function and principle of solder paste inspection machine

SPI yes Solder Paste Inspection For short , It is called solder paste inspection in Chinese , This solder paste inspection machine is similar to what we usually place in SMT After furnace AOI(Auto Optical Inspection) Optical identification device , Optical images are also used to check the quality , principle ： The solder paste inspection machine adds a laser device for measuring the thickness of solder paste , therefore SPI Possible problems and AOI similar , It is necessary to take a piece of panel for visual inspection, and then let the machine take photos as the standard sample , The back board will judge according to the image and data of the first board , Of course, there will be a lot of false positives , So we must constantly modify its parameters , Until the misjudgment rate is reduced to a certain level , So it's not about SPI The machine can be used after you buy it , It must also be maintained by an engineer .

The solder paste inspection machine can only perform surface image inspection , If there is an area covered by an object, it cannot be checked

The solder paste tester can measure the following data ：

Solder paste printing quantity

The height of solder paste printing

Area of solder paste printing / Volume

Smoothness of solder paste printing

The solder paste inspection machine can detect the following defects ：

Whether the solder paste printing is offset (shift)

Whether the solder paste printing height deviates ( Cusp )

Whether the solder paste printing is bridging (Bridge)

Whether the solder paste printing is defective or damaged