Design Of Cushion Packaging For Thin-Type Kitchen Ventilator Via FEM And SRS

Kitchen appliances are subjected to the damage caused by various kinds of shock in distribution.Cushion packaging has drawn more and more attention as it can absorb shock energy and provide protection against shock.In order to find the damage mechanism of products,evaluate the protective performance of packaging,reduce damage to product,cut down the cost of packaging and improve the utilization of materials,research on cushion packaging design for kitchen appliances is studied by taking the thin-type kitchen ventilator as an example in this thesis.During the packaging design process,the core is to determine the shock fragility of the product.According to the fragility of product and cushioning properties of materials,the structural of cushion can be designed.Drop simulation is usually used to verify the cushion to save testing cost.In the case of verifying the responsibility of cushion,the drop test is carried out to further validate.On the basis of the verification results,the cushion configuration is improved.In this thesis,the fragility of the product is obtained by five methods,i.e.,the empirical,non-linear packaging system,test method using cushioning materials,FEM and shock response spectra firstly,which are 108g,147g,116g,120g and 127g respectively.The empirical method and the non-linear cushioning packaging system method are characterized by shortening calculating time and increasing deviation.Although the other three methods have the weakness in test cost or design cycle,the calculation results are reliable.According to the above results,the fragility of the thin-type kitchen ventilator is rounded to 120g.Secondly,cushioning performances of EPE and EPS are obtained by dynamic shock tester.The cushion of thin-type kitchen ventilator is designed in terms of the product characteristics,packaging requirements and cushioning material performance.Firstly,the drop of thin-type kitchen ventilator packaging is simulated under three conditions of corner(2-3-5),edge(3-5)and face 3 through ANSYS Workbench in order to verify the cushion.The energy change of product packaging tracked by solver is in agreement with the law of conservation of energy and such logic as kinetic energy first increasing and then decreasing.Furthermore,the direction of biggest change in velocity and acceleration is consistent with the drop orientation.These two points ensure the rationality of simulated results.The change in maximum displacement,equivalent stress and equivalent strain of packaged product and components are analyzed.It is concluded that the shell is the most easily deformed portion of the product under discussion,and the maximum equivalent stress of the product is also distributed on the shell.Maximum equivalent stress under face 3 is greater than the other two conditions.The equivalent strain on the shell is close to the strain corresponding to the yield point of its own material.Although the cushion can provide protection for the product,the product still has the risk of damage.Secondly,the strength of the package under the three conditions is verified by the drop test.The test results show that the product is safe when it drops under the condition of corner(2-3-5)and edge(3-5).The maximum acceleration of the product exceeds 120 g during the face 3 drop event.Moreover,the obtained acceleration shock response spectrum also exceeds the acceleration shock response spectrum(S_c)when the product fragility is obtained.It can be draw the conclusion that the product will be deformed.The defects in structure of product and design of cushion lead to the drop deformation of thin-type kitchen ventilator.In order to alleviate the shock energy produced by such components as the worm wheel,volute and motor inside the ventilator during the drop test,the improved cushion is placed at the gap between the strainer and volute.The maximum acceleration in product is70 g by the drop test of improved package,which is far less than product fragility.Additionally,the obtained acceleration shock response spectrum is below the S_c of product.Finally,the improved cushion is feasible.