Deign And Experimental Study Of Percussive Shelling Device For Camellia Oleifera Fruit

Camellia oleifera fruit is composed of camellia shell and camellia seeds.The camellia shell is unfavorable to the preparation of camellia oil,therefore,it needs to be dehulled.It is useful for the development of camellia industry that improve mechanic dehulled degree.At present,the main machinery of camellia oleifera fruit in China is extrusion,rolling and impact.It is difficult for extrusion to adjust the extrusion clearance,and the broken shell is easy to cause seed oil seepage and seed shell adhesion.In order to solve the problem of low shell breaking rate and high broken seed rate caused by the difficult adjustment of impact force,a kind of impact type casing breaking device of camellia oleifera fruit in sec-impacted is designed,and research the theories and tests of the machine.(1)In order to decide the way of dehulled and the the structure and size of key parts of machine.Changde "Tiecheng No.1" Camellia were measured.The moisture content of fresh camellia oleifera fruit and the change situation with spreading time.The basic size,quality and density and the initial breaking force of camellia oleifera fruit.The recovery coefficient of camellia oleifera fruit and steel plate.which provides a basis for the mode of broken camellia shell and the determination of the structure and size of key parts of camellia oleifera fruit.Analysis of the above physical parameters,the particle size distribution of Camellia oleifera is wide,and the impact force has nothing to do with the particle size.The collision of the oil tea fruit with the steel plate will cause kinetic energy loss,and the impact type is used.(2)A secondary impact type of shell breaking method was proposed and a tea planter shell breaking device was designed.The overall structure and working principle of the shell-breaking device were determined,and key parts such as rotor,impeller and outer casing were designed.In the structural design of the device,a sufficient impact force is ensured to increase the rate of shelling,and the arc-shaped guide plate is used to effectively reduce the rate of chipping.The basic structure and dimensions of the impeller,rotor and outer casing are determined by designing keycomponents.(3)In order to obtain the main factors affecting the shelling efficiency of camellia,the structural parameters of the shell breaking device were further determined,and the movement and stress of the camellia in the shell cavity were analyzed,and the movement process of camellia in the shell cavity was divided.Several stages were carried out,and the movement and stress of each stage of Camellia oleifera were analyzed,and the relationship between the collision contact force,the trajectory of movement and the structure of the shell breaking device during the movement of Camellia oleifera was obtained.(4)In the part of kinematics and dynamics,the factors that influence the effect of shell breaking are obtained.It is difficult to get the contact force of oil camellia fruit by experiment.Therefore,the collision contact force between camellia oleifera fruit and its rotor is analyzed by EDEM simulation and by comparing the impact contact force between camellia oleifera fruit and rotor at different helix rising angles.Under the different diameter of the outer drum,the contact force between the oil camellia fruit and the outer drum is determined,and the screw lift angle of the impeller and the diameter of the outer drum are determined.By comparing the collision contact force between camellia oleifera fruit and camellia seeds and rotor after broken shell by EDEM,it was verified that the camellia seeds separated from camellia oleifera fruit after the first shell breaking did not break the seeds of camellia oleifera fruit.(5)Test of broken shell performance of camellia oleifera fruit.The main evaluation indexes of camellia oleifera fruit breaking device are shell breaking rate and seed breaking rate of camellia oleifera fruit,that is,in order to achieve higher shell breaking rate and lower broken seed rate,the main axis rotation speed,moisture content of camellia oleifera fruit and installation angle of feed guide plate are used as test factors.A single factor test was carried out;in order to get the influence degree of each factor and determine the parameter combination when the shell breaking effect is the best,the orthogonal test is carried out.The optimized technological parameters are as follows: when the moisture content of camellia oleifera fruit is about 60%,the rotation speed of the spindle is 425 r / min and the installation angle of the guide plateis 75 °,the shell breaking rate can reach 95.37%,and the broken seed rate can be reduced to 4.27%.