摘要
针对深施型液态施肥机扎穴机构始终无法满足喷肥针垂直姿态入出土问题,分别根据卵形非圆齿轮与全正圆齿轮行星轮系的组合啮合特性,设计了一种实现变速垂直扎穴的新型卵形-全正圆齿轮行星系扎穴机构。采用卵形齿轮相互啮合原理,控制扎穴机构在工作周期内的瞬时角速度变化,实现变速扎穴,满足喷肥针在入土与出土过程中水平绝度速度趋近于零的特定要求,达到穴口最小。以喷肥针垂直姿态扎穴并满足小穴口为设计目标,建立机构数学模型,以扎穴机构转速120 r/min、前进速度1.2 m/s和扎穴深度80 mm为约束条件,得到机构的结构参数为卵形齿轮长半轴距离39.9 mm、偏心率0.15、正圆齿轮节曲线直径68 mm和喷肥针长度140 mm,并运用ADAMS软件进行虚拟试验验证。通过高速摄像与扎穴试验,得到喷肥针在前进速度1.2 m/s、扎穴转速120 r/min与扎穴深度80 mm下的轨迹形状、水平绝对速度曲线以及穴口宽度。结果表明,卵形-全正圆齿轮行星系变速扎穴机构在高转速与前进速度下,喷肥针始终保证垂直姿态入出土,实现了小穴口的目标。
Aiming to the problem that picking hole mechanism of deep-fertilization liquid fertilizer applicator can not meet fertilizer-spraying needle inserted and pulled out of soil vertically all the time,according to the meshing characteristic of combining gears for oval non-circular with round gears. A new kind of picking hole mechanism was designed to achieve variable speed and vertical posture at picking hole. The meshing principle of oval gears were used,which controlled every moment change of angular velocity to achieve variable speed picking hole in the working period,the characteristic met specific requirement,which had horizontal velocity of fertilizer-spraying needle trend to zero inserted and pulled out of soil,small hole mouth was achieved. To achieve small hole mouth and picking hole for vertical posture,the mathematics model of mechanism was established,with the rotational speed of picking hole mechanism of 120 r/min,forward speed of 1. 2 m/s and depth of picking hole of 80 mm as constraint conditions,structure parameters of mechanism were obtained,including half shaft distance of oval gear shaft of 39. 9 mm,eccentricity of 0. 15,diameter of circular gear pitch curve of 68 mm and length of fertilizer-spraying needle of 140 mm,and virtual experiment was verified by using the ADAMS software.The experiments of high-speed camera and picking hole were carried out,the trajectory shape of fertilizerspraying needle,curve of level absolute velocity and hole width were obtained when the forward speed was 1. 2 m/s,rotational speed of picking hole mechanism was 120 r/min and depth of picking hole was80 mm,the reasons for the formation of such results were analyzed. Experiments results showed that fertilizerspraying needle still guaranteed the target that had small hole mouth and picking hole for vertical posture.
作者
王金武
周文琪
李鑫
冯金龙
江东璇
王金峰
WANG Jinwu1,ZHOU Wenqi1,LI Xin1,FENG Jinlong2,JIANG Dongxuan1,WANG Jinfeng1(1. College of Engineering, Northeast Agricultural University, Harbin 150030, China;2. College of Engineering, Heilongfiang Bayi Agricultural University, Daqing 163319, Chin)
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2018年第5期136-142,共7页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家自然科学基金项目(51675093)
关键词
液态施肥机
扎穴机构
卵形齿轮
变速扎穴
性能试验
liquid fertilizer applicator
pricking hole mechanism
oval gear
variable speed picking hole
performance experiment
