Actuator Design And Experiment Of Pneumatic Variable-rate Fertilizer Applicator For Topdressing In Rice Production

According to operation in the whole rice growth season usually need to topdressing 2 times,nowadays,the main machine for topdressing in rice is centrifugal disc distributor,this machine has a better width,but has an unstable spread uniformity on working width direction,most of them also cannot fertilize in a variable rate on working width direction.In order to satisfy the needs of variable-rate fertilizer application in rice,use less fertilize to produce more yield,a pneumatic variable-rate fertilizer applicator for rice production,which use outer groove-fertilizer-wheel,and pneumatic fertilizer spreader was designed.This paper aim at its basic properties and fertilization effect and so on has carried on the related experimental research,the main results were as follows:(1)To measure physical properties of the main fertilizer.The proportion of N in urea is more than 46.4 percent,fertilizer particle size in 1 ~ 3 mm is more than 95%,bulk density is 775 g/L,the maximum static friction Angle is 23.5°.The proportion of the compound fertilizer's NPK is 15:6:15,36% of the total nutrient acuity,fertilizer particle size in 1 ~ 4 mm is more than 95%,bulk density is 973 g/L,the maximum static friction Angle is 23.3°.(2)To improve the traditional outer groove-wheel,reduce the distributing volatility of outer groove-wheel.Fertilizer box structure design on the basis of the maximum static friction Angle of the fertilizer,the maximum static friction Angle at the bottom of the dip Angle is greater than the maximum static friction Angle of the fertilizer,effectively reduce the fertilizer box fertilizer residues.Flow fertilizer mixing design the holes in t he joint,not only is advantageous to the airflow distribution box will air evenly distributed to each row fat mouth,can export increases,wind speed,effectively avoid fertilizer congestion,to speed up the fertilizer accelerated motion process,using the principle of venturi fertilizer fertilization,prevent air falling fertilizer mixing tapping by air blow out.Using parallel four-bar linkage for the rise and fall of the fertilizer spray device fixed link,realize the free height adjustment for the fertilizer spray device,designed the fertilizer spray device fixed bar folding structure,convenient operation and walking.(3)Design and test the spraying uniformity of the different structure of baffle fertilizer sprayer.Test results show that the spraying uniformity effect for conical baffle spray device > flat baffle spray device > arc baffle spray device > tri-prism baffle spray device.Under different rotational speed,the same spray evenly effect is also different,the spraying uniformity effect of 30 r/min > 40 r/min > 20 r/min > 10 r/min.(4)Test some basic properties of the machinery.The test results show that the distributing tube length has a significant influence on export of wind speed,when the longer the length,the smaller its export wind speed;Distributing pipe length and distributing mouth height also has a significant effect on distributing the time lag,in the process of the whole machine design,should try to avoid distributing pipe is too long and export height is too high.(5)Experiment the pneumatic type variable machinery group row of each row of fertilizer export fertilizer rate uniformity.Test results show that the distributing structure of grouping independent design there are no significant influence to the row of fertilizer consumption,the whole row of fertilizer consumption can be adjusted by changing the row fat wheel speed fertilizer rate,a single rows per minute fat round fertilizer consumption and distributing the relation between the wheel speed:when the operation speed can be 0.5 m/s ~ 1 m/s,distributing wheel speed in 5 r/min ~ 45 r/min,the fertilizer rate per hectare by distributing coordination realize wheel speed and vehicle speed variable regulation of 16 ~ 411 kg range.(6)Based on the fertilization width and breadth of the machine within the scope of the uniformity of experiment research,the results showed that the fertilization of the machine width can reach more than 9 m,but beyond the limits of 8 meters as fabric width of fertilizer rate is difficult to meet the requirements of fertilizer rate,on the basis of evaluation standard,the optimum fertilization width of 8 meters.