The unloading speed of the packaging scale is completed by the unloading mechanism, also called the feeding mechanism or the feeding mechanism. We know that different packaging scales have different unloading mechanisms, mainly to adapt to materials of different properties. Common unloading mechanisms include: gravity self-flow unloading, spiral unloading, belt unloading, vibration unloading, etc.

The principles of different unloading mechanisms are basically the same, and they all achieve three-level feeding of "coarse feeding", "medium feeding" and "fine feeding" through control. There are also simplified two-level feeding, and the basic principles and control methods are the same. The parameters set on the packaging controller correspond to: "fast feeding advance", "medium feeding advance", "slow feeding advance", and the packaging scale switches the three-level feeding of coarse, medium and fine by collecting dynamic weight data.

Try to shorten the overall time of the three-level feeding while ensuring accuracy. It is easy to understand: "coarse feeding" has a fast feeding speed, but the accuracy is not easy to control. On the contrary, "slow feeding" has easy control of accuracy but the feeding is too slow. Therefore, the key to increasing the feeding speed is to increase the proportion of "coarse feeding". Reduce the proportion of "fine feeding", but not too small. It must be ensured that the work is done when there is sufficient material in the silo. "Fine feeding" can work stably for at least 2 seconds, so that overshoot can be basically avoided.

We know that no matter whether it is coarse, medium or fine feeding, the packaging scale will have a certain overshoot when it stops due to the existence of drop and mechanical inertia. For example, we set the fast addition to add weight to 20KG. When the weight of the packaging scale reaches 20KG, the fast addition stops immediately and then switches to slow addition. If you observe carefully, you will find that when the slow addition starts, the weight is often over 20KG, which may be 21 kg or 22 kg. This is the overshoot of fast addition. Therefore, when we set the medium addition and slow addition, we must set them according to the actual overshoot situation. The overshoot amount when there is more material in the silo of the packaging scale is different from that when there is less material.

In addition to the setting of "fast/medium/slow feeding advance", each feeding mechanism can also be set. The pneumatic gravity self-flowing material door is not convenient to adjust, and the electric one can easily adjust the opening and closing size of the fast, medium, and slow material doors. The spiral feeding can be set by the fast, medium, and slow feeding motor frequency. The belt feeding can be adjusted by setting the inverter to adjust the fast, medium, and slow feeding belt speeds, just like the spiral feeding. The vibration feeding can also adjust the vibration amount by adjusting the vibration frequency of the vibrator.