Design And Experiment Of Film Perforating And Precision Dibbling-planter For Rapeseed

Spring rapeseed production areas are distributed in high latitudes and high altitudes,the regional differences and transition characteristics of the climate are obvious.Based on the application of mulching operation methods in cold and arid regions,combined with the current research situation that film-covered punching machines who are mostly suitable for transplanting vegetables and seeding large-sized seed crops instead of sowing small-size seeds and small-size seeds planters involve less research at home and abroad.In view of the above research progress,this paper proposed and carried out design and experiment of film perforating and precision dibbling-planter for rapeseed.As a multifunctional combined operation machine,it can complete rotary tillage,fertilization and seeding,mulching film and perforating,pressing cover film and other operations.The main research contents of this paper are as follows:(1)Based on a systematic analysis of related domestic and foreign research advances in technologies and equipment in this field,according to the agronomic requirements of rape planting and the requirements of mulching operations,a film perforating and precision dibbling-planter for rapeseed was developed.The main working parameters of the machine were determined and the working process of the machine was analyzed.At the same time,a theoretical analysis of the static interference and the longitudinal stability of the machine were carried out,and it was determined that the horizontal distance of the center of gravity of the machine was 1209.28mm and the center of gravity of the machine was basically located at its horizontal center position,which was slightly closer to the rotary tiller component,the distance from the midpoint was smaller,and the operation was stable.The traditional system of the machine was analyzed,the chain transmission mode and the double-sided ground wheel drive transmission structure were determined.(2)The key technology and working process of the parallel drum support type laminating device were analyzed and explained.The width was 2m and it was convenient to disassemble.It were composed of the double-drum film support device and the molded frame.The structure and size parameters of each component of the parallel drum support type laminating device were determined.The punching method and principle of the roller cone nail combined membrane punch device were analyzed and explained.Based on the mathematical model of the contact area between the conical nail and the film,combined with the high-speed photography technology,the film-breaking ability of the triangle cone nail and rotary cone nail were analyzed and according to the actual film breaking effect,the rotary cone nail was determined to be a conical structure,the structure and parameters of the perforated taper nail and the perforated roller were determined.(3)The key technology and working principle of hole seed metering device were analyzed and explained,and the scoop-type precision hole metering device for rapeseed was selected as seeding device.And the seeding system used a double disc opener as the seeding and ditching device.The main parameters and space layout of the double disc opener were entirely determined.The overall structural layout of the roller cone nail combined membrane punch device was determined according to the lamination-punching method and the space location of the machine.The operation mode and working process of the film-covered and soil-covered device were analyzed and explained,and the film-covered and soil-covered device was designed and improved,the space layout of the film-covered and soil-covered device was determined,therefore the center distance of the film wheel on both sides of the film perforating and precision dibbling-planter for rapeseed was 1.8m,and the center distance of the soil-covered disc of film perforating and precision dibbling-planter for rapeseed was 2.1m.(4)A static simulation analysis of the double-drum film support device and the molded frame were carried out based on the finite element method.The maximum deformation of the double-drum film support device was 0.29mm,the maximum stress was 76.02MPa.The deformation of the molded frame was determined,the maximum value was 2.48mm,and the maximum stress value was 35.64MPa.The simulation results were far less than the rated deformation and stress of each component,indicating that the design of the double-drum film support device and the molded frame were reasonable.The height of the film-covered soil and the width of the film-covered soil were used as indicators.Based on the EDEM discrete element method,a simulation test of the overall design of the film-covered and soil-covered device and the rationality of the spatial layout was carried out.The test results showed that the working height of the film-side soil covering was 38.33mm,and the width of the film-side soil covering operation was91.67mm.The design and the layout of the film-covered and soil-covered device were reasonable.(5)The motion process and the film-hole formation of the roller cone nail combined membrane punch device were analyzed,the key locus of the taper nail was determined to be a long spiral line.The theoretical length of the film hole was 17.32?43.38mm.The performance parameters of affecting the roller cone nail combined membrane punch device was determined.A simulation model of the roller cone nail combined membrane punch device was established by using ADAMS,the motion trajectory and shape of the roller cone nail combined membrane punching device were analyzed and tracked,and the correctness of the theoretical analysis was verified.A single-factor experimental study was conducted on the impact of the diameter of the conical nails,the apex angle of the conical nails,and the radius of the punching roller on the punching performance of the roller cone nail combined membrane punching device based on ADAMS.The experimental results showed that the diameter of the conical nails was 14?18mm,and the apex angle of the conical nails was 47°?53°and the radius of the perforated wheel was60?70mm,the pass rate of the film hole was not less than 86%,the pass rate of the film hole distance was not less than 89.47%,and the punching performance was good.The four-factor three-level L9(3~4)orthogonal experimental method was used and the multi-factor optimization experimental results showed that the optimal parameter combination was:the apex angle of the perforated cone nail was 53°,the diameter of the perforated conical nail was 16mm,the radius of the perforated wheel was 65mm,and the working speed of the machine was 4.17km/h.Based on this simulation parameter combination through the experiment got,the parameter of the experimental index through the parameter optimization was 21.23mm,and the deviation of the film hole spacing was0.29mm.(6)The performance experiment of the film-covered and soil-covered device and the roller cone nail combined membrane punch device,and the field experiment of the film perforating and precision dibbling-planter for rapeseed were carried out.The performance experimental results showed that the width of the soil on the edge of the film was60?100mm,and the thickness of the soil on the edge of the film was 35?50mm,which met the requirements of the film operation.The distance between any two membrane holes was 40?60mm,the length of the membrane holes was 18?30mm,the average membrane hole length was 20.16mm in each row of 1m,and the coefficient of variation of the length of a single row of membrane holes was 3.48%?5.21%.The average film hole spacing within 1m of each row was 51.61mm,the coefficient of variation of the single-line film hole spacing was 2.31%?5.03%,the coefficient of variation of the uniformity of the film hole length of each row was 4.29%,and the coefficient of variation of the uniformity of the film hole spacing of each row was 3.88%,which basically met the sowing of rapeseed acupoint distance and perforated film requirements.Under the working conditions of 18.38%soil moisture content and 2240.8KPa soil solidity,the field experiment measured the seeding rate,the average rapeseed planting density,the pass rate of soil width covered on film side and the pass rate of soil depth covered on film side were respectively 3.86kg/hm~2,59strains/m~2,85%and 90%.The field experimental results showed that the film perforating and precision dibbling-planter for rapeseed could meet the requirements of spring rapeseed film mechanization operation requirements.