Design And Experiment On The Vertical-rollers Header Of Corn

The vertical-rollers header is the central equipment of intelligent self-propelled combine harvester for corn and stalk.The theoretical analysis is made for main equipment of vertical-rollers header.Some primary structure parameters were determined.And the author did a lot of bench tests and field experiment,which provides the basis for the design in corn harvester.The main research contents are as following:(1)Aiming at corn harvester snapping device existing grain bite wounds and grain bite off that caused a serious loss,the author proposed vibration snapping corn method that the snapping bar changes the orientation of corn and then corn will be swing up to break off a simple structure,good snapping effect and high reliability of polygonal vertical-rollers snapping device was designed.And the author studied the mechanism of corn broken caused by vertical snapping.In view of the gripping and conveying device which belongs to the existing vertical corn harvest header with low gripping uniformity,stability and high failure rate,a clearance located gripping and conveying device with simple structure,favorable conveying effect and high reliability was developed.Finally integrated two technologies,completed the vertical-rollers header system’s design and manufacture.(2)Then we analyzed the polygonal vertical-rollers snapping means main structural parameters design method,used orthogonal design method for the number of edges,snapping roll speed and snapping roll diameter tested design.By orthogonal test we know that effect the quality of snapping primary and secondary factors is the number of edges,snapping roll speed and snapping roll diameter.By orthogonal test we could know the optimum combination was that the snapping roll diameter of 7cm,the number of edges of 8,the snapping roll speed of950 r / min.The optimum combinations were tested and we found that the grain broken rate was 0.13%,the grain loss rate was 0.28%,broken stem was 0.53%.The grain losses and damages were both far lower than the national standard.(3)A corn clearance located and conveyed method were proposed and the author analysis the designation method of the main structure and motion parameter of the clearance located gripping and conveying device,explore its main structure and working parameter how to influence the reliability of ordered located conveying and then establish the relevant design theory,which provides a theory reference for design of vertical roller gripping and conveying device.The main parameter influenced the gripping and conveying quality was determined by orthogonal test method which included the clearance of the gripping and conveying track,the velocity of the clearance gripping and conveying chain and the length of the clearance gripping and conveying chain,and the optimal result show that the best combination was that the length of the clearance gripping and conveying chain of 1.3m,the clearance of track of 3.1cm,the velocity of the clearance gripping and conveying chain of 4.5m/s.And the corresponding performance indexes are as following: the success ratio of stem gesture feeding was 92.5%,the ration of break stem was 0.25%,the conveying process was stable and without blocking,which could completely satisfy the requirement of the vertical roller corn reaper.(4)We designed orthogonal experiment with the main kinematic parameters.By orthogonal test we know that effect the quality of snapping primary and secondary factors are snapping roll speed,the velocity of the clearance gripping and conveying chain and the corn stalks of conveying speed.The optimum combination was that snapping roll speed was950r/min,the velocity of the clearance gripping was 4m/s and conveying chain and the corn stalks of conveying speed was 1m/s.The optimum combinations were tested and found that the grain loss rate was 0.29%,the grain broken rate was 0.16%.The grain losses and damages were both far lower than the national standard.(5)Finally we designed and manufactured intelligent self-propelled combine harvester for corn and stalk.The field experiment was carried out.The results showed that the average grain loss rate was 0.188%,the most grain loss rate was 0.28%,the average corn ear loss rate was0.394%,the most corn ear loss rate was 0.91%,the average grain broken rate was 0.142%,the most grain broken rate was 0.19%.The results were better than the national standard.In the process of experiment,the conveying process was stable without blocking.And the machine operating speed can reach 8 km/h,greatly improving the working efficiency.