Device Design For Precise Variable Speed Discharge Of Particulate Matter

With the development of particle automatic discharging production line,a quantitative discharger emerges as the times require,which integrates storage bin,discharging bin,transportation,discharging measurement and quantitative control.It greatly improves the efficiency of food quantitative packaging and brings profits to enterprises.In this paper,after consulting a large number of existing literature,aiming at the problem that the existing discharge equipment is difficult to guarantee discharge accuracy and discharge speed at the same time,presents a solution of a precise variable speed discharging device for particulate matter,which can ensure both the discharging speed and discharging accuracy.The main research work is as follows:(1)The discharging mechanism of material stack height,half-top angle of discharging bin and size of discharging opening is studied by EDEM simulation software.Determine the heap height of the stable material discharge and the half-top angle of the stable material discharge in the blanking bin to improve the accuracy of the discharging material.In order to provide the basis for variable speed blanking,the blanking simulation of different size outlets is carried out to determine the corresponding discharge speed of different outlets.(2)The mathematical model of weighing system is established to determine the impact of dynamic acquisition of symmetrical weight sensor of material impact force.In order to reduce the impact of impact force,the weighing sensor is installed in the lower silo and the data of the symmetrical weight data is filtered in the upper computer.The fluctuation of discharging speed is analyzed when discharging materials at different size discharging ports.Large discharging ports correspond to fast discharging,large discharging speed fluctuation and large discharging error.Three-stage speed regulation scheme is proposed,the first stage speed regulation is large outlet discharge and fast blanking;the second stage speed regulation is fixed outlet discharge and quantitative blanking;and the third stage speed regulation is to strictly control outlet closure by using fuzzy algorithm so as to achieve high precision blanking in the process of outlet closure.(3)A set of quantitative discharging system is designed,including the design of discharging mechanism,hardware design of discharging control device and the design of upper computer discharging platform.Among them,the discharging mechanical device includes the adjustable size mechanism of storage bin,discharging bin and discharging outlet.The weighing sensor,material height sensor and motor are selected and installed.Discharge control device carry out data acquisition,filtering,calculation and upload,establishes simplified model of discharging mechanism,and deduces the function of area of discharging port and motor rotation angle,and fits the function in MATLAB to guide and control the change of size of discharging port.The software of the upper computer discharging platform configures network port,system operation,discharging quality and time setting,and displays the quality curve and the remaining waiting time in real time,so as to realize human-computer interaction.