The Design Of Powder Automatic Feeding System

Powder dosing system has a grate use on food industry, chemical industry, and powder metallurgy industry and so on. There are a lot of problems in Powder packaging process currently such as relatively large error, low rate and seriously environmental pollution. It is necessary to design high-performance powder dosing system to improve the efficiency, environment, the factory's condition, safety and so on. So, it's useful to start our research on the dosing devices.The main tasks in this paper are as follows:Firstly, it analyzes special physical properties of powder and problems in packaging process such as Segregation and bridging. Segregation is due to uneven distribution of powder flow. Segregation results in the larger powder particles disperse in the edge and float on the surface of powder. Bridging means large particles support each other formatting spherical surface because of small particles have been discharged when the powder is in the free discharge.Then, for Special physical properties for powder, it completes the structure design of powder dosing system,3D modeling and finite element analysis. Mainly include batching and hopper components and helical conveyer. By comparison of blanking method and hopper movement form, selecting the vibration hopper of flat rotation, it solves the problems segregation and bridging caused by poor mobility. Screw conveyor which has a simple structure, can achieve a continuous feed. Ii is suitable for powder feeding.Thirdly, on the base of structure design, it designs the hardware of control system. Control section includes feed stepper motor control, vibration motor control, weighing test of hopper, the system parameter setting and display, shut detection and alarm. It completes the design of a switching power supply circuit, display circuit of keyboard, the watchdog reset circuit, and the weight circuit.Lastly, according to the completed circuit, it designs the software of control system including the system main program, initialization routine, the interrupt subroutine, related subroutines and parameters subroutine. It also completes the drawing of flow charts.