At present SMT solder paste detection system on the market a large number of technical, functional and accuracy of the level of missing products. Here, I tell you a simple way to determine the merits of solder paste detector:
* Whether the splint device is blade type. The blade type is moved upwards by the blade mechanism to tighten the circuit board, which can ensure that the upper surface of the circuit board is the base plane. Most of these methods are applied to the equipment with high precision. If the circuit board is pressed down from the top, when the thickness of the circuit board changes, the detection can not get the correct results.
* Whether the rack is cast or steel frame structure. Stable casting or steel frame structure can ensure that the equipment in the long run when their mechanical precision. The structure of the aluminum plate in the use of the process of precision will drift, can not control.
The above two points have been able to initially determine the merits of the system, the following points can help further combing;
* Whether the sampling method is FOV type. As the solder paste detection height to be accurate to the micron level or even smaller, FOV is still taking pictures multiple times, to avoid the mechanical parts and external vibration interference, GGR can reach 6 Sigma 1 micron. Such as the use of the scanning of a single sampling, can not avoid the mechanical transmission and external shocks, the reproducibility of the device itself is very poor accuracy.
* Base selection. The excellent solder paste detection system automatically defines a relative datum for each test point, which is simple and accurate. The second is that the whole board defines an absolute datum by manually selecting more than 3 points, and the operation is complex and inaccurate.
* Automatic detection of the whole board. All the solder paste on the circuit board to detect, in the printing process, for a circuit board is not representative of the point. Good is good, bad is not good. Can not be a point to the situation to estimate the status of hundreds of other points. Solder paste test is to all the points are detected.
* Is it equipped with powerful SPC process control software. XBar-S, XBar-R, Histogram, Single View, Multi View, CP, CPK, G & GR and other reports are indispensable tools.