First, dosing process production control

Reaction tank emulsifier dosage is mainly to control the conveyor system to complete the task of conveying its materials, in the entrance and exit of the material with elevators and conveyor lines. In this way, in the warehouse, production workshop and packaging workshop within the scope of the formation of a smooth access to the various production positions at the same time, but also closed the cycle of the conveyor line system. All relevant materials and finished products used in the production process are finally loaded into bar-coded containers for transportation and loading. Under the action of the production instructions issued by the production management system, the materials enter the conveying dosage from the designated entrance. Overall control requirements: the dosage system consists of hoppers, screw conveyors, detection systems. The dosing device can automatically recognize the truck in place and automatically dosage the truck, and stop dosage automatically when the truck is full. When the material in the hopper is not enough, it stops batching and feeds the material automatically.

The batching process control requirements are as follows.

Initial state

When the mixing system starts, the red light L2 goes out and the green light L1 comes on, indicating that the car is allowed to drive in and load the material. The hopper outlet D2 is closed, if the material level weighing module S1 is set to OFF (the material in the hopper is not full), the feed valve opens to feed (D4 is on). When S1 is set to ON (material in the hopper is full), the feeding is stopped (D4 off). Motor M1, M2, M3 and M4 are OFF.

Loading control

In the process of loading, when the car drives into the loading position, the limit switch SQ1 is set to ON, the red signal light L2 is on, the green light L1 is off; at the same time, the motor M4 is started, after 2S, then M3 is started, then M2 is started after 2S, then M1 is started at the end of 2S, and after 2S, the discharge valve is opened (D2 is on), and materials are discharged through the hopper.

When the car is full, the limit switch SQ2 is ON, the hopper is closed, M1 stops after 2S, M2 stops after M1 stops after 2S, M3 stops after M2 stops after 2S, and M4 finally stops after M3 stops after 2S. At the same time, the red light L2 goes out and the green light L1 comes on, indicating that the car can be driven away.

Stopping control

Close the start SD switch and the whole dosage termination operation of the dosage loading car.

Second, dosage hardware design

I/O configuration and wiring

In order to improve the reliability of kettle dosage and the efficiency of the equipment, PLC is chosen as the dosage controller, according to the requirements of automatic dosage loading control. The motors M1~M4 are controlled by contactors KM1~KM4; in order to facilitate monitoring by the operator, a signal light can also be used to show the running status of the motors.

Three, dosage software design

Structure of PLC control program

Programming with basic logic instructions batching and loading control system, the feed valve is controlled by the material level module S1, S1 no monitoring signal, indicating that the material is not full, after 5S feeding; S1 has a monitoring signal, indicating that the material is full, abort feeding. The start of dosing can be realized by the limit switch SQ1 under the platform scale. When the car drives into the loading position, under its self-weight, it turns on SQ1 and the dosing starts; when the car is loaded to the tonnage, the limit switch SQ2 is disconnected and the dosing stops.

The ladder diagram language is used to prepare the PLC control program. The control program embodies the logistics control method and structure in a clear linear modular approach. It can be divided into the following sections:

① Motion equipment/conveyor path control

All screw conveyors, roller conveyors and elevators are operated in the desired mode to ensure that the cargo boxes can run smoothly and continuously on the conveyor line. According to the route identification code of the containers, control the conveyor line and other conveyor line exchange devices to realize the route selection in the conveyor of the containers.

②Data processing for dosage identification

The barcode laser scanner communicates with the real-time database of the PLC to complete the automatic identification of the containers on the conveyor line.

③Communication interface/real-time database management system for dosage of the host computer

It mainly handles the information exchange with the host computer, including communication protocol, message format, communication coding and decoding, and error diagnosis. Utilize data block to establish record storage area to store the information of cargo box. Utilizing function blocks to realize the operation of the database, providing control basis for the identification of conveying dosage paths.

④Data Processing for MCGS Configuration Monitoring

The data processing in conjunction with MCGS monitoring mainly includes alarm processing, data processing of equipment operation status, and so on.

⑤ Out-of-material change　

When the material of the bin number is finished in the process of dosage, it automatically prompts the missing material alarm. Press [Change bin for lack of material] button, the dialog box will be popped up, input the bin number to be changed, make sure, and then press [Clear fault] button, then the bin will be changed and enter into automatic dosage state. Note: After changing bins, the dosage sequence must be changed. Set the missing bin as 0, and set the new replacement bin number as the same as the original order, so as to facilitate the report statistics.

After analysis, it can be seen that the automatic dosage system is a control process according to a certain sequence of action, using each step can be made strictly in accordance with the sequence of action, if programmed with a stepping instruction program is easier to understand and easier to read.

Conclusion

The dosage system after debugging and operation, the production of materials and automatic distribution capacity can meet the production needs of various products, can meet the relevant logistics company's equipment and production of high-level and high-efficiency operation. The input makes the enterprise completely abandon the manual operation, the batching method into the scientific data production, the individual also from the dust, noise and other harsh labor environment.