The Effect Of The Combined Harvester's Crushing Blade And Dynamic Cutter Clearance On The Crushing Effect Of Wheat Straw Stalk

China has huge amount of crop straw,the proportion of wheat and corn is large.Straw returning technology,can promoting soil fertility?crop yield and improving soil quality,has been widely used in various provinces and cities of China,but our modern farming tools related to the situation seriously restricted the application and development of the straw returning technology.Against the commonly used straw returning machinery in wheat and corn rotation area of China,in order to enhance the quality of straw returning,this article choose a kind of knife straw crusher(model 1JHSX-35)for whole-feeding rice-and-wheat combine harvester,studied the different modes of straw returning and determined the most appropriate mode.Carried out a series of studies:Put forward two kinds of the most appropriate straw returning machinery in wheat and corn rotation area of China,the straw crusher for whole-feeding rice-and-wheat combine harvesters(straw returning mode A)and the horizontal straw chopping and returning machine for tractor(straw returning mode B).Analyzed the research status of straw returning machinery at home and abroad and summarized the deficiencies of our study and some advanced technology overseas.Designed straw crusher,including: designed feeding chamber for connecting straw crusher and combine harvester;built knife roller shaft mechanical model,designed knife rollers;analyzed knife cutting mechanism,determined the key parameters of knife;determined crushing chamber width and shape;designed the transmission system.Finally,determined the bending straight knife straw crusher.Basing on the finite element analysis software ABAQUS,analyzed the mechanical properties of wheat straw and established correlation parameters relational formula.By straw cutting simulation analysis,the minimum speed was more than 2000 r/min,the speed reasonable range of bending straight knife stalk crusher was 3000-3500r/min and the reasonable range of the knife angle was 20°-30°.Carried out crushing wheat straw dynamic simulation,analyzed the movement of wheat straw and straw crushing quality.Basing on LabVIEW and PXI,designed a testing device for the performance of straw crusher,which could detect the power consumption of the different kinds of straw crusher.To set up the test bed,to make the comparison test of straight knife type,bending knife type,straight tooth straw crusher,the results were obtained by means of the data of different knife-type and dynamic test.It is concluded that the bending knife type mill is the best,but the power consumption is the greatest.The straight-tooth straw mill is optimal,the power consumption is reasonable and the crushing effect is excellent.