Research On Design Of Crab Automatic Grading Machine

Crab is a kind of important and precious aquatic product in our country. It has high nutritional values by rich in protein, calcium, phosphorus, potassium,etc.The demand of crabs also increased year by year. With the continuous improvement of people’s living quality, it’s an important part of the goods on our market about the crab weight classification. Artificial weighing classification methods are used frequently. However, due to the high difficulty,low efficiency, big intensity and long time consuming of artificial classification work, it can’t meet the needs of commodity crab season and keeping crab fresh. In order to solve the problems above, this article describes a crab weight classification indexes of automatic classification system designed by ourselves which is based on the studding of automatic grading system in the other areas at home and abroad.In this paper, the research content mainly includes:1.The present situation of the current and prospect commodity market development of crab should be investigated. In reference to other industries classification system, as well as the developing PLC had been widely used in various fields, the demonstration design classification for weight index, based on the necessity, feasibility and importance of the PLC crab automatic control system of classifier, the design principle of classifier were put forward.2.The details of working principle and composition of crab automatic sorting machine was introduced. The use of Auto CAD parts drawings, CATIA3D modeling, the whole institution for ADMAS to carry on the dynamic simulation of the discharge actuator to complete theory of crab automatic classifier design and the choice of important building.3.This paper introduced the crab automatically based on Siemens S7-200series PLC control system of classifier design,and expounds the control step motor using the office module. The hardware design and software design is elaborated on two parts to the grading system of software development. Hardware based on the system control requirements analysis is mainly focused on the hardware structure, the selection of PLC and the hierarchical control circuit design. On the software aspects, it mainly expounds the methods of communication between computer and PLC. The control of the crabs automatic classifier classification system are designed through the STEP7Micro WIN Chinese programming software.4.On the basis of the completed structure design and control system, the crab automatic classifier prototype has been made. It is concluded that the best combination of pickup device for the speed is5r/min, the Angle alpha is10°, Angle beta is130°through rotary pick-up device of orthogonal test, the pick accuracy, production factors such as comprehensive consideration. The classification test are completed under the condition of the optimal combination parameter of crabs automatic classifier. The production test results is grading. The classification is pretty accurate and the damage rate is low.Artificial classification can be replaced by the system.