What are the important parameters of dispensing machine?

In smt chip processing, some special components and processes may have some problems when using the normal solder paste printing process, which will affect the later use efficiency. In order to prevent this problem in advance, we need to do some treatment, so with SMT mounting technology, we need to use dispensing technology. Dispensing machines can be divided into manual and automatic. Manual dispensing machine is used for experiment or small batch production, and automatic dispensing machine is used for large batch production. The following introduces the most important parts of the dispensing machine, the dispensing head and the conventional technical parameters of the dispensing machine.

I. Glue dispensing head

According to the different distribution pumps, the distribution head can be divided into four types: pressure type, screw pump type, linear normal phase displacement pump type and jet pump type.

① Time-pressure dispensing head: For a long time, pneumatic pump is considered as the most direct dispensing method, which works by using the controlled pulse airflow generated by compressor according to the time-pressure principle. It has a syringe with a needle at the end. The longer the air pulse works, the more coating material is pushed out of the needle.

② Glue dispensing head of screw pump: The glue dispensing head of screw pump is flexible, suitable for dropping all kinds of patch glue, insensitive to air mixed in the patch glue, sensitive to viscosity change, and the glue dispensing speed also affects the uniformity of glue dispensing.

③ Linear normal-phase displacement dispensing head: Linear normal-phase displacement dispensing head has good consistency to the glue point during high-speed bonding. It can dispense larger glue, but it is complicated to clean, and it is sensitive to the air in the patch adhesive.

④ Glue dispensing head of jet pump: The glue dispensing head of jet pump is a non-contact glue dispensing head, which is fast in dispensing and insensitive to PCB warping and height change, but the big glue point is slow, requiring multiple injections and complicated to clean.

Second, the conventional technical parameters of the dispensing machine

The conventional technical parameters of the dispensing machine include dispensing quantity, dispensing pressure (back pressure), needle size, distance between needle and PCB, glue temperature, glue degree, curing temperature curve and bubbles, etc.

The above is explained by the technical department of Shenzhen Ouyatuo Electronic Technology Co., Ltd. If you don't understand, you can leave a message (the compilation is not good)