Process method of 3D printing solder paste body on printed circuit board

Abstract

The invention provides a process method for printing soldering paste bodies on a circuit board in a three-dimensional (3D) manner. The process method is a process method capable of accurately printing soldering paste bodies in a three-dimensional (3D) manner. With the process method adopted, the shapes of the soldering paste bodies are controllable, the coating efficiency of soldering paste is high, and different thickness and different shapes can be realized. According to the technical schemes of the invention, the process method is implemented through following manners: a layer of flux of which the shape conforms to the shape of a pad is printed so as to be adopted as a solder powder fixing medium; a layer of solder powder is printed on the flux at a position where the pad is located; after one independent soldering paste body is obtained through layer-by-layer printing, a next soldering paste body is printed; flux layers and solder powder layers which are printed layer by layer are mixed, so that the soldering paste bodies can be formed in real time in a printing process; the flux layers and solder powder layers are printed alternately so as to form required soldering paste bodies; flux is printed at the last layer, so that the 3D printing of the soldering paste is terminated; and flux and solder powder multi-layer liquid naturally compounded soldering paste body layout distribution of different thicknesses and different shapes can be formed on the same printed circuit board.

Description

technical field [0001] The invention relates to the application of solder paste coating in the assembly process of printed boards in electronic products, which is used to realize accurate 3D printing of solder paste bodies with different thicknesses and shapes in the same printed board without missing a printing template. Background technique [0002] Nowadays, electronic assembly technology has generally adopted electronic assembly technology SMT. In a broad sense, the new generation of electronic assembly technology, that is, surface mount technology SMT, includes surface mount components SMC, surface mount devices SMD, surface mount printed circuit boards SMB, ordinary mixed printed circuit boards PCB, dispensing, coating, etc. Technical content such as paste, surface mount equipment, component pick and place system, soldering and online testing, is a collective term for a complete set of technological processes. In the SMT production process, the use of metal stencils t...

AI Technical Summary

Problems solved by technology

[0005] Since the solder paste printing and coating method uses air pressure on the finished solder paste, the solder paste is sprayed on the printed board, and each pad is arranged in a matrix of dot-shaped solder paste to form the final solder paste body, although the solder paste The amount can be controlled according to the size of the pad, but since the solder paste body is composed of multiple dot-shaped solder paste, its shape is uncontrollable, and the poor shape accuracy of the solder paste body makes it easy to short circuit when soldering small packaged devices

In addition, in order to obtain good precision by spraying solder paste, we have to use nozzles with small calibers. The smaller the caliber, the easier it is to clog

Although the solder paste printing does not require the solder paste stencil in the stencil coating method, in this coating method, each solder paste body needs to be sprayed with dot-shaped solder paste multiple times to complete, resulting in poor solder paste coating. The efficiency is very low, the most important thing is that the shape of the solder paste cannot be precisely controlled

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