Before using the automatic dispensing machine, before operating the equipment, the operating personnel of the manufacturer must thoroughly understand the operation of the automatic dispensing machine. Before the engine, check whether the power supply and voltage are stable. After starting up, you should pay attention to whether the machine announces abnormal noise. If so, turn off the machine immediately, and turn on the machine after checking the problem. In order to help us better ensure product quality and improve production efficiency, the following is a summary of the points of knowledge about automatic dispensing machines.

1. According to operating experience, the diameter of the glue dots should be half of the pad spacing, and the diameter of the glue dots after pasting should be 1.5 times the diameter of the glue dots. This ensures that there is sufficient glue to bond the components and avoids excessive glue dipping the pads.

2. If the dispensing pressure is too high, it is easy to cause overflow and excessive glue; if the pressure is too small, there will be intermittent dispensing and leakage, thus forming defects. The pressure should be selected based on the same quality of glue and the temperature of the operating environment. High ambient temperature will reduce the viscosity of the glue and improve its fluidity. In this case, according to the common sense of the automatic dispenser, the back pressure can be reduced to ensure the supply of glue, and vice versa.

3. In fact, the inner diameter of the needle should be 1/2 of the diameter of the glue dispensing point. During the dispensing process, the dispensing needle should be selected according to the size of the pad on the printed circuit board: if the pad size is not different from 0805 and 1206, the same needle can be selected, but different pins should be selected for pads of different sizes. Not only can the quality of glue spots be ensured, but also the production efficiency can be improved.

4. Pitch printed circuit board

Different automatic dispensers use different needles, and some needles have a certain degree of stop. The interval between the needle and the printed circuit board should be calibrated at the beginning of each job, that is, the Z-axis height calibration.　

5. Glue temperature

Generally, epoxy glue should be stored in a refrigerator at 0-5°C. It should be taken out half an hour before use to make the glue completely meet the operating temperature. The operating temperature of the glue should be 23℃-25℃; the ambient temperature has a great influence on the viscosity of the glue. If the temperature is too low, the glue point will become smaller and wire drawing will occur. A 5°C difference in ambient temperature will result in a 50% change in the dispensing volume. Therefore, according to the key points of the automatic dispensing machine, the ambient temperature should be controlled. At the same time, the ambient temperature should be ensured. The glue dots with low humidity are easy to dry and affect the adhesion.