Theoretical And Experimental Research Of Non-ditched Cuttings Transplanting Machine

Ditch-cutting machine's work step is first furrowing and then cutting.The cuttings have not resistance from the soil and cannot be broken.But the deep and wide furrow in the soil of larger spacing between two plants is unnecessary and results in a waste of engine power and the destruction of surface vegetation.In order to save energy and to protect the surface vegetation, non-furrow-cutting machines need to be designed so that the cuttings can be directly inserted into soil. If the soil is too hard for the cuttings to be directly inserted into,a narrow and short ditch should to be open.The main problem faced by non-furrow-cutting machine is deformation of the cuttings because of their moving in the soil and soil resistance.Excessive deformation will cause cuttings to be broken. Therefore the displacement of the cuttings in the soil should be minimized,and the moving track of the cuttings in the soil will be the narrowest in the direction of level.The corresponding mechanism parameters calculated in this paper is for the reason.In addition,the experimental device is designed to validate the best path,got by theoretical study,of the cuttings in the soil,to test the cuttings' strain caused by soil resistance and to master the law of cuttings' force,destruction and deformation. Through different diameters of the actual cuttings inserting into different compaction of soil,the relationships of soil depth,diameter of cuttings,and cuttings tip's sharpness with the soil compaction can be get.All of this lay a foundation for the theory and practice of non-furrow-cutting machine designing.The methods used in the research are the cutting path simulation on various parameters by computer software CAXA,mathematical proof in conjunction with the writing of computer programs on the cutting path and cutting parameters to optimize mechanism,using self-designed experimental equipment,resistance strain gauge,soil compaction meter to test the cuttings' movement track,cutting strain,soil compaction testing,and inserting the actual cuttings into the soil with the cuttings' test machine.On the radial cutting mechanism,when the height H of the center,depth A of cutting,radius R of the imaginary wheel etc.changes,the width M of the cutting path in the direction of the level will change.When the radius R and depth A keep invariable,the height H to a greater or lesser,the width M will make more.The greater the radius R is,the smaller the width M is.The smaller the depth A is, the smaller the width M.When inserting a certain depth,if keep the outline formed by the path of the cuttings the same width on the actual and the imaginary ground,the width of the outline in the soil will be the narrowest.This approach,brought up by the author for the first time,is known as imaginary-and-actual-same-ground-outline-width-method.On the vertical cutting mechanism,the movement track of all points on the cutting plow is decided by the movement track of outside end of the crank set in the mechanism.In a certain radius of the imaginary wheel,the size and shape of the longitudinal section of the movement track of the cutting plow in the soil,the level direction of the cutting plow movement in the soil,relate to the difference of the crank length relative to the radius of imaginary wheel.In the crank length is equal to the radius of imaginary wheel,the movement of cutting plow in the soil is in the forward direction, and the vertical cross-section of the track is sharp and thin and therefore small in area,small in power consumption.The power consumption in the process of cutting plow movement in the soil is of approximately equality.On the vertical cutting mechanism which Inserted cuttings directly into the soil without cutting plow,with super-two-point optimization methods brought up by the author first, the level width of the profile of the cuttings movement in the soil is of minimum,and the best design of the crank length is determined.Inserting cuttings into the soil with the cutting mechanism,the number of cuttings respectively being 3,4,5 when the mechanism rotating every turn,the spacing between two plants being 1m,cuttings depth A into the soil being from 100～250mm,through the optimization,the best value in all of crank length and the mechanism's center height are calculated.With the device self-designed,the radial cutting track is verified being exactly the same with the theory deduced.Using the data of three-point bending experiment of the actual cuttings,steel cutting specimen is designed to test cuttings' bending strain.By cuttings' destructive bending test,it is found that cuttings' destruction happened at the cross-section next to where the cutting is gripped,and cuttings were pulling off by the normal stress caused by bending moment,and the tensile strength of the cuttings is lower than the compressive strength.In addition,the load end deflection of the cuttings before damage is larger than 100mm.Soil compaction is a very difficult to simulate,the concept of the soil equivalent compaction and its method of calculating is proposed for the evaluation of soil compaction.By cuttings' speed and force analysis,it is known that the pressure and friction of soil on the cuttings' bar is the main factors that cause the damage of the cuttings.Inserting the steel sample into the soil for bending strain,it shows that strain of the sample along the length of the cuttings linear increases,and the maximum is at the gripping end of the specimen when inserting to the deepest.The greater the soil compaction,the greater the strain is.Analysis and practice has proved that,when the actual cuttings inserting into soil,if the soil equivalent compaction being enough great,the cuttings' damage occurs in the gripping end.If the soil compaction being smaller,the cuttings will not be damaged,but there will be some bending at the holding end,the remains part of cuttings in the soil will maintain a straight line and tilt.By cutting test machine,inserting the actual cuttings into soil,it is clear that the smaller the inserting depth,the easier it is inserted into the soil.Cuttings' end,whether sharpened or not,has not much difference.12-16mm diameter of the cuttings,when inserting into the soil,have almost the same degree of difficulty. CAXA software is used in this study to simulate the cuttings path of the cutting mechanism when it dealing with different parameters.Mathematical methods are used for strict derivation and demonstration of the track and its changing law of cuttings in radial cutting mechanism,of the cutting plow or cuttings in vertical cutting mechanism.Proposed the point of view of 'Same Contour Width on Imaginary and Actual Ground Optimization' and 'Super-Two Optimization'.In conjunction with the methods of preparation of the computer program to the cutting mechanism parameters optimization,the best mechanism parameters are arrived at.With the experimental equipment designed for the cutting mechanism as well as soil compaction meter,the track of the cuttings movement in the soil has experimental verification.Combind with experiment,'soil equivalent compaction' and its method of calculating is proposed.Through the experimental study of cuttings' bending strain,the conception of cuttings' 'soil-pressure-point' and 'soil-push-point' are proposed to analyse the cuttings' force,deformation and destruction.With the cutting machine,inserting actual cuttings into soil,the relation of the cutting diameter,inserting depth of soil,and the cuttings end sharpness with the soil compaction can be got.All of the methods and the results of the research in China have not been reported innovative.