Solder paste printing, as being the 1st primary procedure of SMT chip processing, includes a immediate effect over the processing top quality. Among them, 60% from the defects appear within the printing excellent, and its significance is self-evident. Consequently, it is actually very significant for operators to grasp the process things of automatic solder paste printing machine. Currently, Shenzhen Zhichi technological know-how will describe the process aspects of automated solder paste printing device.

1?¡é Graphic alignment of printed circuit board

The optical positioning position (mark point) of the base plate and also the metal mesh to the workbench is aligned with the printing equipment digital camera, after which you can the X, y, |¨¨ high-quality adjustment from the foundation plate as well as the metal mesh is carried out, to make sure that the bottom plate pad sample and also the steel mesh opening sample are completely coincident.

2?¡é Clarification of angle between scraper and circuit board in printing

The more compact the angle concerning the scraper as well as metal mesh, the larger the downward force. It can be effortless to inject the solder paste into your mesh, nonetheless it can be quick to squeeze the solder paste into the bottom from the metal mesh, leading to paste adhesion, which is generally 45 ~ sixty levels.

3?¡é The quantity of solder paste enter (rolling diameter of solder paste) in the operation of computerized solder paste printing machine

1. The rolling diameter of solder paste ?¨® h ?? ten ~ 15mm is appropriate.

two. When the rolling diameter ?¨® h is too small, it really is easy to cause solder paste leakage and less tin material.

3. If your rolling diameter ?¨® h is just too big, far too much solder paste can not sort rolling movement, plus the solder paste cannot be scraped clean up, causing weak printing demoulding and thick solder paste after printing; and excessive solder paste subjected to the air for years is destructive for the quality of solder paste.

four. In manufacturing, the operator visually checks the amount of solder paste about the mesh plate each and every 50 percent one hour, moves the solder paste beyond the stroke from the scraper over the mesh plate which has a shovel blade each and every 50 % an hour, and distributes the solder paste evenly, but cant shovel it to the opening with the metal mesh.

4?¡é The stress of scraper once the computerized solder paste printing machine functions

Scraper force is likewise a significant variable affecting the printing excellent. The tension in the scraper essentially refers back to the depth of the decrease from the scraper. If your force is simply too smaller, the scraper wont adhere into the metal mesh surface, so it can be equivalent to escalating the printing thickness. Moreover, if the tension is too smaller, a layer of solder paste will stay on the surface on the steel mesh, that is effortless to bring about printing flaws these kinds of as bonding (bridging) along with other printing flaws.

GKg automatic solder paste printing equipment

5?¡é Printing velocity of automated solder paste printing device

one. Since the velocity of scraper is inversely proportional to the viscosity of solder paste, the speed is slower when theres a slim spacing. If the velocity is too fast, time for that scraper to pass through the metal mesh opening is relatively limited, plus the solder paste can not fully penetrate into the opening, which is effortless to bring about printing defects these kinds of as insufficient solder paste forming or lacking printing.

2. There is a specified partnership concerning the printing velocity as well as the force on the scraper. Reducing the printing pace is comparable to raising the pressure.

three. The perfect scraper velocity and pressure should be to only scrape the solder paste from the floor of your wire mesh.

6?¡é Printing gap of computerized solder paste printing device

The printing hole is definitely the distance concerning the steel mesh and PCB, that is linked into the retention of solder paste on PCB soon after printing.

7?¡é Separation velocity of steel mesh and PCB in computerized solder paste printing equipment

Soon after solder paste printing, the instantaneous speed of metal mesh leaving PCB is the separation speed, which can be a parameter relevant to printing excellent, and it is the key in dense spacing and higher density printing. The superior printing equipment has one (or maybe more) micro dwell processes when the metal mesh leaves the solder paste pattern, i.e. multi-stage demoulding, so as to guarantee the very best printing forming.

When the separation velocity is simply too large, the adhesive drive of solder paste decreases, as well as the cohesion involving solder paste and pad is small, that makes some solder paste stay with the underside of metal mesh as well as the wall of opening, causing printing problems this sort of as deficiency of printing and tin collapse.

Once the separation velocity is gradual down, the solder paste has superior viscosity and cohesion, that makes the paste conveniently break away through the steel mesh opening wall, and also the printing state is nice.

8?¡é Cleaning method and frequency of computerized solder paste printing machine

Cleaning the underside of the metal mesh can also be a factor to make certain the printing high-quality. The cleaning mode and frequency must be established as outlined by the solder paste, mesh materials, thickness and gap measurement. (established dry cleansing, wet cleaning, one-time reciprocating, wiping velocity, etcetera.)

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