Design And Experimental Research Of Peeling Machine For Imitating Contour Of Lotus Root

Lotus root is one of the characteristic aquatic vegetables in China.After harvest,it needs to clean and peel,then it can be sold directly or made into prepared dishes.At present,the peeling of lotus root mainly relies on manual labor,which is high labor intensity and high labor cost.Moreover,due to the different shapes and sizes of lotus root,the existing mechanical peeling methods still have the problems of low cleaning rate,high peeling loss rate and low surface smoothness after peeling.To solve the above problems,this paper takes E lian No.5 as the research object to design a rotary peeling machine of imitating contour of lotus root.The structural parameters of its key components are designed and analyzed and the working mechanism of the whole machine is studied,the prototype is trial-produced and the whole machine performance test is carried out.The main research contents are as follows.(1)Experimental study on mechanical properties of lotus root skinThe contour of lotus root was measured and the surface mechanical properties of lotus root were tested.The texture analyzer was used to carry out all-factor tests with peeling cutting maximum force as evaluation index,cutting direction,sampling site and loading speed as experimental factors.With tensile fracture maximum strength as evaluation index and sampling site and tensile direction as test factors,a full factor test was carried out.The body length,width and height of lotus root were 98.16～238.57 mm,62.51～91.11 mm,57.57～86.48 mm.And the moisture content of peel was 80.46%～86.28%.Sampling location and loading speed have significant effects on peeling cutting force and cutting direction has significant effects on peeling cutting force.The cutting direction has significant influence on the tensile strength of lotus root skin.And the axial tensile strength is stronger than the circumferential one.By improving the cutting speed,the cutting resistance can be reduced and the efficiency of mechanical peeling can be improved.(2)Design of the peeling machine of imitating contour of lotus root.The peeling scheme design of lotus root was carried out,and the peeling method was determined to be lotus root rotation and tool copying movement.The structure and size of the key parts of the peeling machine are determined.Then a imtating pendulum rod mechanism and an arc cutter which is connected with the pendulum rod with finite depth support block were designed.The peeling process was analyzed theoretically.Combined with the simulation analysis of Recur Dyn,the cutting speed is more stable and it has less stop time when the rotation speed of lotus root is in the range of 70～130 r/min.By improving the shape of different depth limiting support blocks,combining the peeling stability and tool fit of different depth limiting support structures,the optimal depth limiting support structure is determined as rounded corner type.(3)Design of control system of peeling machineThe hardware selection and software design of the electric and pneumatic control system of the peeling machine were carried out,and the automatic operational process of lotus root feeding,feeding,peeling and blanking was realized.The software of manmachine interaction interface is developed to facilitate real-time observation and adjustment of operation parameters.(4)Performance tests of peeling machine of lotus root Through experiments,the main factors affecting and the optimal parameter range of effect of peeling machine were obtained.Single factor tests were carried out,which is the supporting structure with different depth limits of the tool.And the best peeling effect was the round-corner deep limit supporting tool.On this basis,Box-Behnken response surface tests were carried out with the peeling uniformity and peeling loss rate were taken as the test indexes.And the lotus root speed,stepper motor speed and torsion spring wire diameter was as the test factors.At last the optimal parameter verification tests were carried out.The results showed that when the lotus root speed was 108 r/min,the lead screw speed was 74r/min and the torsion spring wire diameter was 1.6 mm,the peeling uniformity of lotus root was the best.Under this condition,the peeling loss rate was 11.6%,and the cleanliness rate of peeling was more than 85%.The results can provide reference for the research design of peeling machinery of lotus root.