Design And Test Of Key Device Of Double-blade Hami Melon Peeling Machine

In China,as currently the main peeling method for Hami melon is artificial peeling,not only the efficiency is low,but also there are some health and safety problems,which seriously hinder the innovation and development of Hami melon products of related enterprises.In order to reduce the labor intensity of workers and improve the peeling efficiency and mechanization of Hami melon.In this paper,a double-knife Hami melon peeler with strong adaptability,simple structure,convenient operation,uniform peeling and high peeling efficiency is designed.The main research work of this paper is as follows:(1)Research on physical characteristics of Hami melon.Statistical analysis was carried out on the long-axis diameter,short-axis diameter and skin thickness of Hami melon "Cucumber Dream Crisp".It was determined that the average long-axis diameter,short-axis diameter and skin thickness of Hami melon were241.86mm,148.33mm and 5.61mm respectively,and the corresponding size distribution diagram was drawn.And according to the skewness and peak coefficient,the long-axis diameter and skin thickness of Hami melon were determined.The size distribution of short axis diameter and skin thickness of melon obey normal distribution.(2)Force analysis of Hami melon.Through force analysis,it is determined that Hami melon is mainly subjected to cutting force and axial force from the cutter body,and the axial force Ft is proportional to the short end of the cutter rod L2 and the copying force F0,and inversely proportional to the long end of the cutter rod L1.In addition,the Hami melon is also subjected to the clamping force,extrusion force and rotating force of the three clamping jaws of the positioning fork.The clamping force of fruit holder on Hami melon is mainly related to gravity.(3)Design and improvement of key devices.The length of the tool rod and the maximum elongation of the spring in the profiling mechanism are designed and calculated.It is determined that the length of the tool rod is 300mm at the long end,110mm at the short end and 27.5mm at the maximum elongation of the spring.The positioning fork is designed and improved by reducing the chassis diameter of the claw disc and adopting the circular claw structure.The holding fruit clamp improves its stability and safety by increasing the effective length and contact area of the holding block.The cutter is designed as a curved zigzag according to the curved surface principle in Triz theory.(4)Test and parameter optimization.Carry out orthogonal test and regression test on frequency of fruit drive motor,frequency of cutter motor and cut-in angle.Primary and secondary order of each factor is A(frequency of fruit drive motor)>B(frequency of cutter motor)>C(cut-in angle).The best combination is A2B2C1.Through multiple linear regression analysis,the regression equation between test factors and test indexes is obtained.The optimum values are as follows: frequency of fruit drive motor is 32 Hz,frequency of cutter motor is 25 Hz and cut-in angle is 26 °.The result of verification test shows that the highest peeling rate is 94.1% and the average peeling rate is 91.1%.The peeling is relatively uniform,which proves the rationality of theoretical parameter analysis and structural design of the double-knife Hami melon peeler.