The Performance Experimental Study On High-fineness And Toughness Crop Of Tangential-axial Flow Threshing Device

High-fineness and toughness stem crops are characterized by small stem diameter,large stem toughness and plant height,the representative crops are oat,millet,barley,buckwheat and other miscellaneous grain crops.In the process of traditional whole feeding combine harvesting for high-fineness and toughness crops,because of the mismatch of some key parameters of threshing device,the stalks of high-fineness and toughness crops are often wound around the threshing cylinder,resulting in the winding and blockage,which affects the operation efficiency slightly,and even causes the damage of the machine parts.The lack of special threshing equipment for high-fineness and toughness stalk crops has become a key problem restricting the rapid development of high-fineness and toughness crop industry in China.In order to solve the problem of stem winding cylinder in the process of threshing,a tangential-axial flow threshing device for high-fineness and toughness crops was proposed in this paper,to confirm the key parameters of threshing device for high-fine and toughness crops,oats were selected as representative crops in this paper.Firstly,a large number of tests and experiments were carried out on the physical characteristics of oat stalks.Then,the threshing scheme and the structure of the whole machine were determined on the basis of these tests.Finally,a set of threshing test-bed for high-fine and toughness crops was designed and manufactured,and the related parameters were tested.The research contents are as follows:(1)The physical and mechanical properties of oats were measured and studies,the parameters of oats such as plant height,stem diameter,node number,node diameter and material moisture content were obtained.(2)Based on the study of the physical properties of oat stalk,the combined structure of tangential-axial flow threshing device was conformed of high-fineness and toughness crops,and the overall structure and main components of the threshing cylinder of high-fineness and toughness crops were designed.(3)Study on threshing and winding resistance of tangential cylinder.Taking oats as the research object,the single factor experiment was carried out,and the influence rules of each experimental factor on the test index was analyzed.On the basis of single factor experiment,orthogonal experiment of three factors and three levels was conducted,visual analysis and variance analysis were carried out on the experimental results,and the optimal combination of parameters was obtained.Finally,on the basis of orthogonal experiment,fixed threshing elements,selected cylinder speed and threshing clearance as test factors,regression test was carried out,and the mathematical model between test indexes and test factors was established.The mathematical model was combined by comprehensive evaluation method,and the optimal combination of motion parameters was obtained.(4)The effect of the relative position of two cylinders on the threshing performance and winding resistance of high-fineness and toughness crop shearing-axial threshing device was studied.The parameters of the two tangential cylinders were fixed in the test,and the position matching test of the two cylinders was carried out,the relative position of the two cylinders and the rotational speed of the axial flow cylinder were selected as the test factors.The experiment was divided into three parts: contrast test of single factor,orthogonal test and verification test.