Design And Experimental Research On The Anti-clogging Pickup Of Long Straw Square Bale Baler

China is a large agricultural country with abundant crop straw resources.In recent years,with the rapid development of industrial and commercial areas and the continuous increase in the output of various crops,people’s demand for crop stalks has decreased,and large amounts of stalks produced by wheat,rice and corn with larger yields have remained.Because of its low density and looseness,it is difficult to collect and transport in the commercialization process,the utilization rate of straw in my country is extremely low.The baler is a collection and storage machine that integrates crop straw picking,conveying,compression and bundling.The pickup is one of the key components of the baler and the first process of the baling operation.Its function is to continuously pick up the straw to the rear auger.The quality of the picking effect directly affects the working performance of the baler.This article takes 9YFQ-2250 square baler produced by World Group as the research object.In order to solve the problems of clogging of long straws in the gaps of the retainers and accumulation of straws in blind areas on both sides of the auger during the picking process,two structures without retainers were proposed.And carried out three-dimensional modeling,simulation analysis,prototype manufacturing and experimental research on the two schemes.The main research contents are as follows:(1)The key components of World Group’s 9YFQ-2250 square strapping machine were analyzed,and three-dimensional modeling was performed on them through Solid Works,and the whole structure and working process of the strapping machine were introduced.(2)Analyze the movement law of the end of the spring tooth when the original pickup was operating in situ.It is clear that the contraction change of the spring tooth is determined by the change of the cam slide swing angleθ,and the equation expression of the cam slide swing angleθwas obtained.Analyzing the law of the absolute movement of the end of the elastic tooth during the operation,it was concluded that the three factors that affect the picking operation are the forward speed of the baler,the speed of the pickup and the radius of the picking drum.(3)Through a large number of field experiments,the reasons for the clogging of the original pickup and the characteristics of easy clogging of straw were summarized,and the design requirements and performance evaluation standards of the anti-clogging pickup were put forward.(4)Determine the plan of the elastic tooth pickup without guard ring and slide track,design the structural parameters of the key components and build the 3D model with Solid Works;Perform theoretical analysis on the movement trajectory of the elastic teeth and the movement of the straw during picking operation to determine the feasibility of the plan;The kinematics simulation analysis of the scheme was carried out through ADAMS,and the theoretical analysis of the feasibility of the scheme was verified,and it was proved that the spiral arrangement of spring teeth can play the role of picking up and gathering straw inward;Manufacture prototypes and conduct field pick-up tests.The tests showed that:For short straws,this solution is feasible without clogging;while for long and tough straws,the gap between the transition plates will be blocked during the picking process,indicating that it is unreasonable to cancel the cam slide.(5)In view of the blockage problem summarized in the test of the elastic tooth pickup without guard ring and slide track,the plan of the elastic tooth pickup without guard ring with cam slide was determined.Use the"reversal method"to design the cam slide,design the structural parameters of the drive shaft assembly,the rack assembly and the arc welded plate assembly and establish a three-dimensional model.Perform kinematics analysis on the posture of the spring tooth in a single period and compare it with the motion trajectory of the spring tooth in the theoretical analysis to verify the rationality of the cam design;Perform simulation analysis on the motion parameters of the pendulum to describe the different stages of the spring tooth motion;Perform force analysis on the no-load state of the cam slide,and find its maximum force point,which is 1380N;A test bench was designed to carry out a field test of picking up long rice straw.The test showed that:The new scheme can carry out the picking operation stably without clogging.Assemble this pickup prototype to 9YFQ-2250 baler for field test,it was measured that the average bale time for straight operation is 20.06s,the average bale distance is 4.62m,the average volume of the bale is 0.097m~3,the average mass is 18kg,and the average density is 185.57kg/m~3.