Design And Test Of Double Roller Differential Dry Pepper Picker

With the continuous increase of pepper planting area in recent years,the planting is gradually large-scale,and the output is the first in the world.At present,when the pepper is harvested,it needs to be picked manually,which wastes a lot of labor.In the world,machines often use the way of beating the pepper fruit to make the pepper fall off,the color of the pepper is not good,and there are many damages to the pepper,which reduces the quality of pepper picking,and there are still potential safety hazards.Therefore,in view of these problems,a pair of roller differential pepper fruit picker is designed.This study can reduce the damage of pepper fruit and reduce potential safety hazards.The main research contents and conclusions are as follows:(1)The moisture content of the pepper fruit and the mechanical characteristics parameters of the pepper fruit were measured to provide reference parameter values for the later design of the whole machine.The biological characteristics of the pepper were measured,and the length of the pepper fruit was about 4.5-6.5 cm and the diameter was 0.8-1.3 cm.Experimental measurements of the mechanical characteristics parameters were conducted,and it was concluded that the force required to pull off the pepper fruit from the stalk was on average greater than that required to pull off the fruit from the stalk to the stalk;tensile and shear tests of the pepper fruit were conducted to obtain the average tensile and shear strengths of the pepper.After the formula calculation the results show that: when the moisture content of chili pepper fruit is around 40%,the force it can withstand is the largest,when the chili pepper picking effect can be better.The friction coefficient between pepper fruit and rubber roller is also measured and compared,and the friction effect between pepper fruit and different rubber roller coatings is obtained,and considering the elasticity and other factors,silicone rubber roller is finally chosen.(2)The design of roll differential speed dry pepper picking machine.The machine mainly includes transmission device,picking device,cleaning device,frame,inlet and outlet,etc.The machine adopts the way of differential speed rotation of rollers for picking chili pepper fruits,and then separates chili pepper fruits from stalks and branches and leaves through the cleaning device to reduce the impurities contained in the final chili pepper fruits.The structure of the key parts of the machine,such as picking device,cleaning device and frame,is elaborated theoretically.For the design of the transmission part,a chain is used for transmission and the variation of speed between the four stages of rubber rollers is realized by the cooperation of sprockets of different sizes.(3)The theoretical force analysis of pepper fruit picking process is carried out,and the simulation and analysis of pepper fruit picking process is based on EDEM.The discrete element model of pepper fruit and stalk is established,and the parameters of the simulation model are calibrated using EDEM,and then imported into the simulation machine model for simulation tests for analysis.By setting different rubber roller speed and spring tensioning distance,the single-factor test of the pepper picking machine was carried out,and the analysis showed that the picking rate increased with the increase of rubber roller speed and spring tensioning distance,and the breakage rate increased with the increase of rubber roller speed and spring tensioning distance,and the best picking effect was obtained when the speed was 2.5m/s.(4)The trial and test of dried chili pepper fruit picking machine.Through three-factor and three-level orthogonal experiments,we determined the test factors of water content of chili pepper fruit,rubber roller speed and spring tension distance,and the response values of picking rate,damage rate and impurity rate as test responses,and derived the correspondence between each test factor and each test response.After software preference and testing of the picking test,the picking rate of the picking machine was 94.54%,the damage rate 1.17% and the trash rate12.25% at a water content of 41.94%,a rubber roller speed of 2.03 m/s,and an elastic compression distance of 30 mm.