Design And Experiment Of Compound Cutting Parts Of Tobacco Hilling Machine

For tobacco,com,sugarcane and other high stalk crops,the ability of lodging resistance and yield can be enhanced by soil cultivation.At present,the technology of cultivating soil in machinery is of low efficiency,low efficiency and high energy consumption.The cultivator uses the cutter to loosen the soil,throw it to the top of the ridge,and complete the cultivation,so that the bottom of the ditch is hard and there is no loose soil,which is easy to cause the loss of the original water in the soil.And when encountering rainfall,the hard soil can’t effectively realize the function of water storage,thus producing rainfall runoff,resulting in soil erosion.In this paper,based on a large number of domestic and foreign literature on the cultivation machinery,combined with the relevant agricultural requirements of the mechanical cultivation operation,a tobacco hilling machine was designed and developed,and the method of composite cutting soil was put forward.At the same time,the composite cutting parts were analyzed and tested.The specific research content of this paper mainly includes the following four aspects:(1)With the help of the cutting theory and characteristics of metal materials,a new mechanism was designed to realize the composite cutting of soil,which adopts the composite operation mode of the soil plough and the spiral cultivator to cut the soil.As the machine moves along the direction of the ridge,the cutting edge at the bottom of the plow is not perpendicular to the cutting direction,forming oblique cutting;the spiral knife is inclined along the direction of the ridge side,and the spiral knife rotates rapidly to realize the milling and soil breaking of the ridge and the ridge side;the oblique cutting and the spiral milling form a composite cutting.(2)In this paper,the interaction behavior of two cutting methods,oblique cutting and spiral milling,was studied and optimized.The starting angle δ of the plow is 30°,which is good for cutting soil;the spiral angleβof the plow is 73.4°,which meets the requirement of reducing power consumption;the angle a between the guide bar and the horizontal plane in the guide cover device is 30°,which is good for soil guidance.Based on the optimization analysis of the layout and combination of the two kinds of cutters,it is concluded that the pre delivery of the plow is loose soil,the post delivery of the spiral knife is broken soil,and the spiral knife adopts the "V" shape layout,establishes the composite cutting model,forms a new composite cutting method,improves the soil crushing rate of the ridge body,and reduces the operation energy consumption.(3)Based on the discrete element method,the model of soil interaction between the working parts of the machine and the soil was established.The soil flow control part composed of the composite cutting parts of the tobacco cultivator and cultivator was simulated and analyzed by using the EDEM software.The influence of the linear velocity along the outer of spiral knife v0 and the forward velocity of the machine vm on the effect of the cultivator was studied by using the two factor comprehensive experimental design method.The results of DEM simulation show that the linear velocity along the outer of spiral knife and the forward velocity of the machine have a very significant impact on the particles and the thickness of the soil;the multiple comparison of the average soil thickness shows that the linear velocity along the outer of spiral knife and the forward velocity of the machine have a very significant impact on the particles and the thickness of the soil;the multiple comparison of the average soil thickness shows that:When the linear velocity along the outer of spiral knife v0 is 3.01m/s and the forward velocity of the machine vm is 0.7m/s,the energy consumption of the implement is small,the performance of the implement is ideal,and the work efficiency is satisfied.At this time,the total number of soil particles transported to the top of the ridge is 157,the number of bottom particles transported to the top of the ridge is 75,and the thickness of the soil is 40mm,so the comprehensive operation effect is good.(4)The three-dimensional solid model of the whole machine was established,the prototype trial production was completed,and through many field experiments without crops,the compound cutting parts of tobacco hilling machine were tested,the three-layer flow control system was analyzed,and the effect of the guiding cover device on the flow direction of soil was tested and verified.At the same time,the field experiment was carried out.Through the experiment of the thickness,inclination and height of the compound cutting parts of tobacco hilling machine,the field experiment results showed that the field experiment results were basically consistent with the simulation experiment results,which met the requirements of the cultivation operation and agronomy.