Improvement And Experiment Of Soil Covering Device For Straw Covering Machine In Orchard

With the continuous development of apple dwarf planting technology,it is becoming more and more important to study the supporting soil management methods and work tools.The development of mechanized layered cover technology and equipment for orchard stalks is conducive to the realization of resource utilization of straw and the improvement of operational efficiency.In this paper,the performance of a new generation of dwarfing orchard straw delaminating covering machine testing device was studied.A feasible scheme was proposed for the existing problems and the main components were designed and simulated.Then the modeling of the soil covering device was completed.Prototype processing,and finally carried out experimental research,the main research results obtained are as follows:(1)Through the research on the performance of a new generation of testing machine's soil covering device,we found that the main problems are: large volume of the soil shovel,uneven soil distribution,and easy jamming due to unbalanced force when the soil lifting components are scraped and shoveled.The phenomenon.Based on the existing problems,two schemes of spiral subsoil throwing and earth throwing are proposed.Based on the analysis,the spiral subsoil throwing plan is determined;it is mainly composed of sub-soil spirals,throwing wheels and uniform earth spirals.Such as the composition,the advantage is a simple structure,small size,throwing soil throwing soil to solve the scraper easy to die.(2)Discrete element simulations were performed on the key parts of the spiral soil-trigger throwing type soil covering device,the soil-separating screw and the throwing wheel.The results showed that: Uniformity: Continuity of soil throwing increases with increasing number of blades,but when the number of blades exceeds 10,the throwing space of the soil is reduced,resulting in a decrease in soil throwing distance;when the throwing wheel rotates At 206r/min,the horizontal distance and the total horizontal distance of the highest point of the throwing soil decrease with the increase of the throwing angle under the condition that the target throw height is 0.4m within the throwing angle range of 40° to 50°.Small,but the height of the highest point of throwing soil is constantly increasing.(3)Prototype development was carried out on the earth-covering device,and a singlefactor test was conducted on the rotational speed of the caster,the throwing angle and the depth of subsoil spiral entry with the standard deviation of the cover soil thickness as a measure.The single factor test results in the range of throwing angle of 30° to 50° indicate that the standard deviation of thickness is the minimum when the throwing angle is 40°,and the optimal test range of the throwing angle is 35°~45°;in 200~300r/ The single-factor test results within the min speed range show that the minimum standard deviation of thickness is 250 r/min,and the optimal test range of speed is 250~300 r/min.The single factor test results within the depth range of 2~6cm into the soil indicate that the standard deviation of the thickness is the minimum when the depth of the soil is 2cm,and the optimal range of the depth of the soil is 2~4cm.(4)Response surface analysis method was used to measure the standard deviation of cover soil thickness as an index to test rotating speed,throwing angle and depth of soil penetration.The results showed that the optimal parameter combination of soil covering device was 300 r/min.The throwing angle is 39.7° and the depth of the soil is 2cm.Three groups of repeated experiments are performed under the optimal combination.The standard deviation of the cover soil thickness is 3.68,which is close to the predicted value of 3.65.This indicates that the model is well fitted and can be used to predict the cover soil.Happening.(5)The coefficient of variation of soil test data for the first generation tester and the spiral soil throwing type soil covering device were 54.6% and 35.5%,respectively,indicating that the soil covering uniformity of the spiral soil throwing type soil covering device is better than that of the first generation testing machine.