With the technological innovation of electronic products, the trend of miniaturization, these PCBs of electronic products turn more and more intensive, chip and package become more and more small. Designers are looking for ways to shrink PCBs. This poses a challenge to PCB manufacturers, how to better and faster to put paste solder paste on the graphics precision, conductive adhesive and filling watering under. Automatic dispenser came into being. So how to better choose and use automatic dispenser?
1, Needle Specifications and Categories
Needle size will affect the dispenser in the dispensing process and the precision of the glue, In a certain range, the greater the pressure of the needle tip of the mouth, the greater the rate of plastic, so according to the size of the products produced to determine the specifications of the dispensing needle. General diameter of the spot diameter is the half of the spot size, the effect is the best.
2, The Impact of Bubbles
In the dispensing process, sometimes the glue will be mixed into the air, resulting in air bubbles, the product will be out of defective products. In order to eliminate the adverse effect of the bubbles, the bubble generation can be prevented to a certain extent by centrifugal treatment or vacuum evacuation, or by adding a protective layer.
3, Curing Factors
For the glue curing conditions, should be carefully confirmed before production, according to their product characteristics, equipment and other factors to choose glue. In practical application should be possible to meet the selection of glue curing conditions, so that after curing glue has sufficient strength and hardness.
4, The Pressure
The thicker the glue, the greater the pressure required. So we should be based on the production process temperature and the amount of dispensing glue size to adjust the pressure.
5, The Size of Glue
The amount of dispensing is determined by the duration of the dispensing process, the longer the time, the greater the amount of dispensing. A suitable amount of glue to ensure adequate viscosity and can avoid the waste caused by too much glue.
In the PCB assembly and PCB manufacturing process, the choice of the right dispenser is very important. The above is based on our own experience summed up, I hope that can help you.