Design Of Clamping Finger-chain Type Device For Recycling Agricultural Plastic Film

Mulching planting technology is a new type of farming technology and has been widely applied in crop planting.It not only brings huge economic benefits to agricultural production,but also causes serious pollution to agricultural ecological environment.The domestic equipment for recycling agricultural plastic film has the problems that the recovery rate of plastic film is low,plastic film is easily to wrap the film collecting parts,the straw and soil is difficult to be separated from the film,in addition,the effect of film removing is poor and high impurity content of recovered plastic film can not be recycled.The structural dimensions and operating parameters of main components were designed and studied by theoretical analysis and experimental method.Then the performance of the device was test through field experiment.These indexes met the technical requirements of the plastic film recovery and this device could be used for the development of a new type of residual film recycling machine.The cotton planting pattern and film mulching were obtained by field investigation in Xinjiang province.Through the tensile test on agricultural residual plastic film(0.01mm)samples,The maximum value of tensile force was 3.41 N when the residual film was broken.According to the whole structure and working principle of device,the size parameters of key components of film collecting device and film removing device were determined through theoretical analysis and experimental study.The parts model of film collecting device were established by Solidworks 3D software.Then the three-dimensional solid model film collecting device was assembled to verify whether the relationship was reasonable.The trajectory equations of the finger tip were obtained through the kinematics analysis of film collecting process,The calculation formulas of absolute acceleration,speed,the penetration depth of finger,the scratch length of finger were obtained by derivation.It was determined that the working length of finger was 165 mm,the ratio of clamping-chain speed to machine operating speed k was 0.6,and the depth of clamping-chain finger entering into soil was 77.3 ~ 83.6mm.Based on the mechanism analysis of film removing device,it is determined that the position relationship between the parts and the working speed of film shaft n2 was 220r/min.According to the k value,the transmission system was designed and the transmission ratio of film collecting transmission system was allocated.According to the structural parameters and working parameters of clamping finger-chain type device for recycling agricultural plastic film,three main factors affecting the film collection rate were determined.The combination experiment was carried out under Box-Behnken experimental design principle,and then multiple regression fitting analysis was carried out.Through the response surface analysis,the influence of three factors on the recycling rate were as follows: the working length of clamping finger,the ratio of clamping-chain speed to machine operating speed k,the machine operating speed.Through the parameter optimization,the optimal parameter combination was determined.The working length of clamping finger was 160 mm,the ratio of clamping-chain speed to machine operating speed k was 0.7,and the machine operating speed was 4.7km/h.The field experiment showed that the residual film recycling rate could reach91.05%.Comparing with the parameter optimization value,the relative error of the parameters was less than 2%,and it verified that the model was reliability.When the working speed of film shaft n2 was220r/min,the removal rate of residual plastic film could reach 98.74 %.