Study On A New Type Of Corn Ear Picking Device

Corn ear picking device is an important part of the corn harvest machine. The workingprinciple of the existing corn ear picking device is to rely on the extrusion and tension ofsnapping roll on the ear and stalk of corn, which is easy to cause the corn ear nibbling. At thesame time, because of the extrusion and serious crush of snapping roll on the corn stalk, it isnot conducive to the recovery and subsequent field work management. Therefore, our grouppresented a bending and fracture corn snapping method in order to solve the above problems,which is based on the working principle of breaking off the corn ear artificially. The keytechnology is to hold the corn stalk by the holding and conveying device and apply lateralthrust on corn ear by the snapping roll, then make the corn ear bend to the corn stalk in orderto realize the fracture between ear and handle. According to the above principles, weexplored a new type of corn ear picking device, developed test bench and tested the snappingeffect in this paper.Firstly, determine the transmission scheme and the overall layout of test bench. For thecorn stalk with good passing through performance, test bench also has the following threefunctions:1、adjust the relative angle between the snapping roll and holding and conveyingdevice;2、change the speed of holding and conveying device with variable speed motor;3、change the speed of two snapping roll on the left and right sides alone. According to the testrequirements, carry out design computing and power selection on each key component oftest bench and complete the design of2D drawing.Secondly, according to the design of2D drawing strictly, build3D part model. Thenbuild the virtual prototype with3D part model. If find something wrong, correct immediatelyafter comprehensive consideration. This paper introduced the modeling and assemblyprocess of some harder parts during building3D virtual prototype. The common functions ofthe CATIA can be understood and the3D structure of the test bench also can be furtherrecognized.Then, carry out simulation analysis for holding and conveying device of the cornsnapping test bench. Simplify model in CATIA and import it into RECUDYN software. InRECURDYN, set up material properties, define constraint vice, add drive or load and builddynamic conditions and environment of simulation prototype. Then, through the dynamiccontrast analysis of prototype, study the motion law of model, optimize design parametersand lay the foundation for the study of the working process of the system. Finally, according to the preparatory work such as design and simulation in front, makethe test bench. Carry out the corn snapping test using the test bench. And carry out theorthogonal experiments of three levels and three factors. The factors are the speed ofsnapping roll, the speed of holding and conveying belt and the angle between the holdingand conveying belt and snapping roll. Consider the interaction between the speed ofsnapping roll and holding and conveying belt. The levels of each factor are as follows: thespeed of snapping roll are11r/s,13r/s and15r/s; the speed of holding and conveying belt are9r/s,11r/s and13r/s; the angles are35°,40°,45°. Adopt the experiment optimizationdesign method to optimize and analyse the experiment and the optimal combination is asfollows: the speed of snapping roll is11r/s, the speed of holding and conveying belt is11r/sand the angle between the holding and conveying belt and snapping roll is45°. Calculate theequation of each factor on experimental indexes with regression method. As can be seenfrom the equation, the holding and conveying belt and the angle have secondary effect to thepicking rate and the angle between the holding and conveying device and the snapping rollhas greater influence on picking rate.The research work provides support for the research of a new type of corn ear pickingdevice, also provides the research basis for the development of corn harvest technique andenriches the corn harvest technology.