What are the important parameters of the dispensing machine

In smt mounting processing, some special components and processes using normal solder paste printing process may appear some problem points, so as to affect the effectiveness of the later use. In order to prevent such problems in advance, you need to do some processing, then with the SMT SMD process, you need to use the dispensing process. Dispenser can be divided into manual and automatic two kinds of manual dispenser for test or small batch production, automatic dispenser for mass production. The following is an introduction to the dispensing machine in the most important parts of the dispensing head and dispensing machine of the conventional technical parameters.

A, dispensing head

Dispensing head according to the distribution of different pumps can be divided into time - pressure type, screw pump, linear positive phase displacement pump, jet pump type 4 kinds.

①Time-a-pressure type dispensing head: For a long time, the air pressure pump has been considered the most direct way of dispensing, which works according to the principle of time-pressure, using a compressor to generate a controlled pulse airflow. It has a syringe, equipped with a needle at the end, the longer the airflow pulsation works, the more the number of coated materials launched from the needle

② Spiral Pump Dispensing Head: Spiral Pump Dispensing Head flexibility, suitable for drip coating of a variety of patch adhesive, patch adhesive mixed in the air is not too sensitive, but the viscosity of the change in the sensitivity, the speed of the coating on the consistency of the coating also has an impact on the dot.

③Linear positive phase displacement dispensing head: linear positive phase displacement dispensing head high-speed dispensing on the glue point consistency is good, can point a large glue point but the cleaning complexity of the patch adhesive in the air sensitive.

④Jet pump type dispensing head: jet pump type belongs to the non-contact dispensing head, fast dispensing speed, the PCB warping and height change is not sensitive, but the speed of the large glue point is slow, the need for many times to spray, cleaning complex.

Two, the regular technical parameters of the dispenser

The regular technical parameters of the dispenser point of the size of the amount of glue, dispensing pressure (back pressure), needle size, the distance between the needle and the PCB board, the temperature of the glue, glue, the degree of curing temperature curve and bubbles, etc.