Optimization Design And Test Of Seeder Of Rotary Tillage Knife Type Corn Precision No-tillage Seeder

Corn precision no-tillage seeder is one of the important tools for the whole mechanization of corn,which can complete the rotary tillage of corn,stubble breaking,ditching,fertilization,sowing and suppression of corn at one time.During the working process of the corn precision no-tillage seeder,the vibration caused by the unevenness of the ground surface,the forward speed of the seeder and the rotary tillage speed reduce the seeding performance of the discharger and affect the sowing quality.In view of the above problems,this paper analyzes the research status of the vibration characteristics of corn seeders at home and abroad,takes the rotary tillage knife corn precision no-tillage seeder as the research object,collects the vibration signal of the corn no-tillage seeder when working in the field,designs the vibration test bench of the seeder and carries out the vibration test of the finger clip seeder,explores the influence of various factors on the sowing quality of the finger clip seeder,optimizes the key components of the finger clip seeder,and uses EDEM and Recur Dyn coupling technology.The seeding performance of the finger clamp seeder under vibration conditions was simulated,and the working performance of the seeder was verified by bench test.The main research contents and conclusions are as follows:(1)In this paper,the vibration signal of the rotary broadcaster under the actual work in the field was collected by the vibration test system,and the actual field vibration information of the rotary knife no-tillage seeder was filtered and time-frequency analyzed by Matlab,and the time domain analysis results showed that the rotational tillage speed and operation speed had a significant influence on the vibration acceleration.The order of influence is: the rotary tillage speed is greater than the operating speed.The secondary integration of vibration acceleration shows that the maximum vibration displacement of the seeder is 16.004 mm.The results of frequency domain analysis show that the vibration frequency distribution of no-tillage seeder is between 0-100 Hz.(2)On the basis of test analysis,the design scheme of the vibration test bench is proposed,and the vibration test of the ejector is carried out.The motor and cam are selected as the main vibration source,and the cam and spring driven by the motor cooperate with each other to simulate the vibration environment of the seeder during field operation.The seeder detector is connected to the seeder by means of a rigid coupling and an elastic coupling,and drives the finger clip seeder.The vibration test results of the finger clamp seeder show that the working speed,vibration amplitude and vibration frequency have significant effects on the qualified index and missed broadcast index of the seeder.The order of factors affecting the qualified index of the seeder is: vibration amplitude,working speed,vibration frequency;The order of the missed broadcast index is: vibration amplitude,vibration frequency,operating speed.(3)Through experimental analysis,the key components of the finger clip seeder were optimized,and a multi-arc finger clip and a seed plate with boss were designed,and the structure of the finger clip seeder was modeled in three dimensions.Through the force analysis of the seeds,with the increase of the rotation angle of the finger clamp,the holding force of the finger clamp shows a trend of first increasing and then decreasing,and the support force is the greatest when the finger clamp passes through the top of the seed tray.It verifies that the structure of the designed seeder is reasonable.The simulation test of the seeder in the maize sowing process was carried out by EDEM and Recur Dyn coupling method,and the movement process of maize grain in the process of seeding,filling and carrying was simulated,and the movement speed of maize grain under vibration conditions,the movement trajectory of individual maize and the entire maize grain population were obtained by post-treatment.The analysis results show that by optimizing the finger clamp and seed tray,so as to hold the grain through the combined force of pressure and support,the corn grain can be effectively prevented from falling off the finger clamp during the seeding process.The optimized seeder results in a higher conformity index during the seeding process.(4)The seeding performance of the optimized seeder was verified through bench test.Using the combined test of seeder performance tester and vibration test bench,the operating speed,vibration amplitude and vibration frequency of the seeder were used as the test factors,and the qualified index,missed broadcast index and replay index were used as the evaluation index,and the single-factor test and multi-factor test were carried out respectively.The results of single-factor test show that the working speed,vibration amplitude and vibration frequency have a significant impact on the qualified index,missed broadcast index and replay index,and the multi-factor test shows that the interaction terms of working speed and vibration amplitude,vibration amplitude and vibration frequency have a significant impact on the qualified index.The interaction terms of operating speed and vibration amplitude,and the interaction terms of operating speed and vibration frequency have a significant impact on the missed index.The test results are optimized and solved,and when the working speed is 2km/h,the vibration amplitude is 6.21 mm,and the vibration frequency is 33.85 Hz,the qualification index is 93.9%,and the missed broadcast index is 6.94%.The finger clip seeder is optimized to meet the design requirements.