Study On Low-damage Cleaning Mechanism And Equipment For Whole-leaf Vegetables

A new vegetable washing machine was designed for the cleaning needs of whole leafy vegetables.It can effectively reduce the damage of whole-leaf vegetables in cleaning process under the premise of ensuring high cleaning rate.Moreover,It can extend shelf-life and easy to pack after cleaning.The process and methods of vegetable cleaning were studied.On the basis of analyzing the current situation of vegetable cleaning at home and abroad,choose bubble and water flow type cleaning,basket cleaning method,basket lifting type transport,and baric drive.The cleaning process is a periodic vibration mode,which simulates the process of manually cleaning the vegetables in the basket.Draw a working cycle diagram.The overall structure of vegetable washing machine was studied.The structure of cleaning tank,water circulating filtration unit,air bath cleaning device,and basket lifting device was desiged.The parameter and types of pump,fan,linear slider,and cylinder were carried out.CFD analysis was performed on the cleaning flow field.The influence of flow velocity and jet line parameters,such as diameter and spacing,on the cistribution of convective field was studied.It results that,witih the increase of airflow velocity,the number of bubbles is increased,and the gas holdup increases.Moreover the disturbance amplitude at the liquid level increases.The gas phase distribution in the water of the cleaning pool is at the best level when the airflow velocity is 6m/s,the diameter of the hole is 8mm and the spacing is 50mm.The control system was designed.The design of pneumatic circuit and the selection of components was carried out.Block diagram of electronic control system,I/O mouth distribution,sequence flow diagram,and ladder diagram of PLC was carried out.The program and online simulation debugging of touch screen were carried out.The structure and circuit connection of electric control box were carried out.Prototype production and tests were studied.The 3D solid model,engineering drawings,and prototype production of vegetable cleaning were carried out.Experiment results show that the cleaning rate is 92.28%and the breakage rate is 7.46%when washing volume is 5kg,cleaning time is 120s,and gas bath strength is 6 m/s,whch is the optimum cleaning process parameter.