The printing accuracy of the automatic solder paste printers depends on several key parts of the internal structure of the machine:

1. Cleaning part of the stencil

All automatic solder paste printers use three methods of dry,wet and vacuum cleaning.With the development of surface mount technology, the gap between PCBA pads is getting small, the production speed of the entire SMT line is fast, and Icicle and tin-connection on the PCB have a lot to do with cleaning. The quality of automatic cleaning is directly related to the quality of the product, and the improvement of the cleaning function can realize the high efficiency of production speed.

In recent years, automatic solder paste printers have undergone significant improvements in cleaning. The independent cleaning structure and the new cleaning concept, including the vacuum adsorption system of the powerful exhaust fan, the more uniform alcohol injection system, and the more efficient cleaning method, can realize the benign continuity of printing.

2. The image positioning part

The quality of image positioning depends on the positioning algorithm, which is also one of the core algorithms of the machine. As the production efficiency of PCB is getting higher and higher, the electronic components on the board are getting smaller and smaller, and higher requirements are also placed on the positioning accuracy and speed.

At present, most of the positioning algorithms of SMT automatic solder paste printers on the market are based on image grayscale and realized by autocorrelation matching. For copper-clad boards with good surface uniformity, the grayscale algorithm can perform the automatic positioning function well. However, the emergence of more and more tin-plated, gold-plated and flexible PCB boards brings huge challenges to grayscale positioning.

3. Snap-off methods of stencil

The quality of snap-off directly affects the printing effect. Generally, automatic solder paste printers have two snap-off methods:

1. "Squeegee first and then snap-off", which is more commonly used, mainly for relatively simple PCB

2. "Snap-off first and then squeegee"

3. The squeegee released first, maintaining the pre-pressure value, and then snap-off