Research On Control System Of Continuous Fruits And Vegetables Puffing Equipment

The principle of low temperature differential pressure puffing was fruits andvegetables materials were heated by heater under the condition of high pressureair flow. It was puffed by the way of instantaneous pressure when reached therequired temperature. In order to solve intermittent production, uneven heatingand puffing parameters unstable control problems of the low temperaturedifferential fruits and vegetables puffing equipment on the market at present, aset of the fruits and vegetables puffing equipment was designed which couldrealize continuous work. Based on PID control of temperature parameters etc.inthe process of fruits and vegetables were puffed, and a variety of fruits andvegetables material parameters were called flexibly, continuous fruits andvegetables puffing equipment could be controlled automatically that ensured thequality of puffing and increased the productivity of the expansion.In this thesis, we study the content of the specific summarized as follows:（1）On the basis of mechanism design and type selection on fruits andvegetables puffing equipment.Various parts were modeled respectively by Pro/Eand the simulation was carried on.（2）Jujube were produced in Shanbei which were selected to conductswelling experiments.On the basis of single factor experiment,the best extrusiontemperature, extrusion pressure, vacuum drying temperature, vacuum dryingtime could be got by three factors three levels orthogonal experiment. Because ofthe experiment equipment time, the environment, test and so on, Otherparameters of multiple fruits and vegetables materials were collected byextruding technology literature, and made the process parameters table, realizedreal-time call in the upper machine.（3）Control system of the whole equipment was designed based on S7-300PLC.The whole control system could be divided into weighing system, far infrared heating system, vacuum puffing system, cooling system and call systemparameters. Five systems were designed and software programmed by STEP7V5.4software hardware, and the simulation were run by STEP7-Win V5.4PLCSIM.（4）Temperature control system of far infrared heating system in fruits andvegetables puffing equipment,which was monitored by industrial computer.This thesis implemented automated production of fruits and vegetablespuffing equipment，through the study on the modular design of control system，ensure the reliability of the fruit and vegetable puffing system.