The Key Technology Of Tow-type Square Baling Straw-wrapped Net Baling Machine

With the increasing utilization of straw,the demand of straw in many industries is also gradually increasing,so it is needed to collect a large number of straw transport.Direct transportation and storage of straws after baling is easy to lead to the occurrence of straw material scattered and so on,which reduces the reliability of transportation and storage quality.In order to ensure the stability of the transport quality of straw after baling,it is necessary to wrap or wrap the surface of straw after compression baling.At present,there are many researches on envelop machinery of round straw baling machine,most of which are equipped with separate envelop machinery for envelop operation.However,at present,there are few researches on the enveloping or wrapping operation of square baling machine,and there is a lack of integrated machinery for the baling and wrapping operation.In this thesis,aiming at the mechanical problem of square baling machine’s integration operation,a square baling straw binding net baling machine is developed.The main research contents include:1.Explore a treatment method of square bale straw baling and net integration,that is,install a net winding mechanism on the baling machine,re-design the straw material transmission,and realize the automatic net winding of the straw in the baling process,which includes conveying mechanism,compression mechanism and net winding mechanism.The conveying mechanism feeds the crushed straw into the compression baling chamber to prepare for the subsequent extrusion;The compression mechanism extrudes the straw into bundles through the piston.The piston size of the core component is 370mm×290mm,the length of the crank r=300mm,and the length of the connecting rod L=885mm.The mesh winding mechanism is installed in the discharge port of the baling room.With the discharge of the bale,it touches the sensor 1-4,and the mesh winding device carries out the corresponding action.After completing the mesh winding operation,the cutter reaches out to cut off the mesh.2.Simulation analysis of key components.In order to verify whether the designed compression mechanism has the characteristics of quick return and whether each component satisfies the stress condition under no-load condition,this paper uses the solid works motion and solid works simulation modules to conduct the simulation analysis of the motion characteristics and no-load force of the crank,connecting rod and piston in the compression mechanism.The results show that the extrusion time of the piston is 0.4s and the return time is 0.25s,which verifies the quick return characteristics of the compression piston.The minimum safety factors of the base,crank,connecting rod and piston are 2.291,8.811,2.028 and 1.579,respectively,which meet the design and use requirements of agricultural machinery.At the same time,in order to further obtain the stress conditions of each part of the compression mechanism in the process of compression,this thesis uses Recurdyn-EDEM-ANSYS coupling method to verify.The results show that the equivalent stress of the extrusion chamber is 0.2767MPa,the maximum deformation is about 0.0012mm,and the equivalent stress of the piston is 173.44MPa.The maximum deformation is about0.66mm,the yield strength of the structural steel is 235MPa,and the parts will not be damaged during the extrusion process.3.Field performance test was carried out on the bundling and wrapping machine.The results showed that the consumption of mesh was affected by the power consumption and time of the mesh,the consumption of mesh increased significantly with the increase of the time of the mesh,the bundling rate was 99.4%,the regular bundling rate was 96%,the anti-fall rate was 93%and the density of the bale was170kg/m~3,which met the requirements of the national standard.