[0020] like figure 1 As shown, a raw material distribution and measurement control device for a belt scale includes a belt scale 5, the belt scale 5 is connected to a weighing control instrument 1, and the weighing control instrument 1 is connected to a programmable logic controller 2, the programmable logic controller 2 Connect the material distribution monitoring computer 3.
[0021] Among them, the belt scale 5 adopts SA-600 8-unit array belt scale produced by Nanjing Sanai Company. The belt scale 5 is composed of an array of multiple weighing units, which can work reliably in harsh environments and has extremely high weighing stability. The error can be kept within 2‰ for a long time. The weighing control instrument 1 adopts the 201H weighing instrument produced by Nanjing Sanai Company. The weighing control instrument 1 adopts 87C520 CPU and 24-bit A/D converter, and its function is such that the PID current output can be passed through the governor or frequency converter. It can control the speed of various slip motors and AC motors, and can be used in combination with the weighing frame of belt scale 1 of various specifications to continuously measure and quantitatively batch various bulk raw materials. The weighing control instrument 1 has a 4-20ma standard current output function, and the current signal can be connected to the analog input module of the programmable logic controller 2 through a cable. The programmable logic controller 2 adopts the American Rockwell ControlLogix5000 series PLC. Compared with other microcomputers, the programmable logic controller 2 is more suitable for running in harsh industrial environments, and the data processing function is greatly enhanced. With modular function, it can solve the problems of local programming, monitoring, communication, etc. The programmable logic controller 2 processes the 4~20mA current signal sent by the on-site weighing control instrument, and obtains the instantaneous amount of the belt scale, Batch accumulation, class accumulation, daily accumulation and other data. The material distribution monitoring computer 3 adopts Advantech ARK series industrial computer, which meets the advantages of continuous, high efficiency, and long failure-free time in the industrial field. It can realize data exchange with the programmable logic controller 2 through Ethernet. Computer 3 can select key data such as the variety, manufacturer, shipping unit, receiving unit, picking method, and starting time of each batch of materials. Clear and save, and at the same time, monitor the belt material flow in real time through the material distribution monitoring computer 3, and judge and control the feeding quantity based on this.
[0022] The above-mentioned control method of the raw material distribution metering control device of the belt scale, a. The weighing control instrument 1 is installed on the site, the programmable logic controller 2 is installed in the control cabinet of the control room, and the material distribution monitoring computer 3 is installed in the scheduling operation. On the table, the belt scale 5 is installed on the bracket of the material conveying belt conveyor 4. The signal of the belt scale 5 is sent to the weighing control instrument 1 through the signal cable 7, and the weighing signal is sent to the programmable logic controller 2 through the signal cable 7. The material distribution monitoring computer 3 communicates with the programmable logic controller 2 through the Ethernet communication cable 8;
[0023] b. When the material is conveyed on the material conveying belt conveyor 4, the dispatcher selects the variety of the supplied material, the delivery unit, the receiving unit, the material manufacturer, the picking method, the cargo location, and the key parameters of the starting time through the monitoring screen of the material distribution monitoring computer. , the programmable logic controller 2 processes the current signal sent by the on-site weighing control instrument 1, and after the program operation of the programmable logic controller 2, the accumulated amount is fed back to the material field scheduling in real time through the material distribution monitoring computer 3, and the material is conveyed. After completion, the material yard dispatcher clicks the "Clear" button through the material distribution monitoring computer 3, and the programmable logic controller 2 completes the accumulation of the weight of the batch of materials, and stores the batch data in the local database of the material distribution monitoring computer 3. for inquiries.
[0024] Programmable logic controller 2 can complete the calculation of shift accumulation and daily accumulation for each material, and finally output shift report and daily report.
[0025] Body weight measurement method:
[0026] When the material starts to be conveyed, the material yard dispatcher selects the material type, manufacturer, shipping unit, receiving unit, and reclaiming method through the material distribution monitoring computer 3, and clicks the "Start" button to obtain the starting time of material loading. PLC 2 pairs The feeding amount starts to accumulate. The formula for calculating the cumulative amount of the belt scale:
[0027] (kg) ----------------- (1)
[0028] Among them, W—the weight of the unit belt feeding, kg/m
[0029] v—the running speed of the belt, m/s
[0030] Assume that the length of the material transport belt is l and the running time is t l , at time t l The weight of the material conveyed inside is Q. According to formula (1), as long as the weight of the unit belt feeding and the speed of the belt are measured, the time t can be obtained. l The value of W can be measured by the weight sensor, the measured value is an analog quantity, and the value of v can be measured according to the speed sensor.
[0031]After the material transportation is completed, the material yard dispatcher clicks the "Clear" button through the material distribution monitoring computer 3, and PLC 2 completes the accumulation of the weight of this batch of materials, and saves the batch data into the local database of the material distribution monitoring computer 3.
