Weighing system by microcomputer weighing and comparison, and output control signal, perform fixed value weighing, control the operation of the external feeding system, the implementation of weighing and rapid packaging tasks. Weighing system adopts MCS-51 single chip microcomputer and V/F voltage frequency converter and other electronic devices, 8031 is used as the central processor, BCD code plate is used as the fixed value setting input, the material is installed in the hopper, its weight causes deformation of the elastic body of the weighing module, the output of the electrical signal proportional to the weight, the output signal of the weighing sensor is amplified by the amplifier. The input V/F converter performs A/D conversion, and the converted frequency signal is directly sent to the 8031 microprocessor, and its digital quantity is processed by the microcomputer. On the one hand, the computer sends the instantaneous digital quantity of the weight into the display circuit to show the instantaneous weight, on the other hand, it makes a weighing comparison, opens and closes the feeding port, and puts the material in the box.

In the whole fixed dosing system, the strain gauge load cell is used in the weighing module. Four positive strain gauges constitute the whole bridge. When the added bridge pressure U is unchanged, the output signal of the sensor is proportional to the gravity acting on the sensor and the bridge pressure of the supply bridge, and the change of the bridge pressure U is direct

It affects the measurement accuracy of the Electronic scale, so the bridge pressure is required to be stable. After amplification, the millivolt sensor output becomes the voltage signal output of 0-10V, which is sent to the V/F converter for A/D conversion, and the frequency signal output by the output end is added to the counting and input terminal T1 of the MCU 8031 timer 1. Timer 0 is used as the counting time in the microcomputer, and the timing time of timer 0 is set by the required A/D conversion resolution. The value of timer 1 reflects the measured voltage, i.e. the weight of the material. In the display at the same time, the computer also according to the set value

Make a fixed value judgment with the measured value. The measured value is compared with the given value, the difference is taken to provide PID operation, and when the weight is insufficient, the feed continues and the measured value is displayed. The weight of a day is equal to or large dry given value, the control interface outputs the control signal, controls the external feeding equipment to stop feeding, displays the final value of the measurement, and then issues an answer order, indicating that the bag is finished, and the bag can be loaded and weighed.

It is an automatic weighing and loading device. Each charging box or bag moves along the conveyor belt until the electronic weight of the material is loaded, the conveyor belt stops moving, the electromagnetic coil 2 is energized, the electronic weight hopper is turned over, so that all the material is poured into the box or bag, when the material is poured out, the conveyor motor is energized again, and the full material box or bag is moved out, and the conveyor belt is protected to continue running. Until the next empty bag or empty box cut off the light source of the photoelectric sensor, at the same time, the electronic weighing box is reset, the electromagnetic coil 1 is energized, the funnel automatically feeds the electronic scale, the weight is controlled by the microcomputer, when the material in the electronic scale is equal to the given value, the electromagnetic coil 1 is powered off, and the spring force makes the funnel door close. The charging system begins the next charging cycle. When there are enough materials in the funnel and enough boxes on the conveyor belt, the process can continue continuously. If necessary, the staff can stop the conveyor belt at any time, enter different given values through the dial, and then start again, you can change the weight in the box or bag.

Weighing system practical functions:

1. Real-time display of temperature, pressure, liquid level, weight, volume and other parameters, and according to the conditions of the storage tank to make the corresponding ultra-high or ultra-low alarm;

2. Integrate various control functions, such as pump and valve control, alarm system, with storage tank history query and curve changes, and archive;

3. With the special interface of MES, ERP and other enterprise office software, it can carry out warehouse management, inventory management, procurement management, cost management, etc.;

4. Upload the data to the cloud server through the network, and the real-time status of the storage tank can be monitored anytime and anywhere.