玉米直插穴播机强排-强启排种装置设计与试验

在玉米直插穴播机的基础上,针对被动鸭嘴开启过程播种性能受地面高低起伏影响较大的问题,设计了强排-强启排种装置,主要由共轭凸轮、强排-强启排种器等组成。对前进速度补偿机构进行了分析,确定了穴播过程关键时间点,重点对强排-强启排种器的取种轮取种和鸭嘴强制开启2个动作实现进行了位移计算,反求法计算确定共轭凸轮的主凸轮轮廓;取种轮匀速转动能提高取种率,通过计算确定了凸轮从动件运动规律。试验结果表明:该装置传动运行平稳,能完成取种和排种动作,鸭嘴无夹土、无提早排种现象;鸭嘴膜孔较小,鸭嘴播种期间无挑膜、撕膜等问题;玉米直插穴播机的空穴率为1.8%、穴粒数合格率为95.3%、膜下播种深度合格率为88.1%,设计的玉米直插穴播机强排-强启排种装置满足设计要求和玉米播种的农艺技术要求。

Design and Test of Metering Device with Forced Seeding and Opening for Corn Direct Seeding Machine

On the base of corn insert plot hill-drop planter, in the light of sowing performance of passive duckbill opening is greatly affected by the fluctuation of ground level, a strong row-strong open metering device was designed, which is mainly composed of conjugate cam, strong platoon-strong open metering device. The sowing process of forward speed compensation device of corn insert plot hill-drop planter was analyzed to determine the key sowing time points. The displacement calculation of two kinds of movements of connecting rod and fetching seed wheel and opening forcibly of duckbill were carried out emphatically. According to the calculation results with reverse calculation method, the main cam profile of the conjugate cam was determined. A uniform rotation wheel can improve the rate of movement of the cam follower, and the motion law of cam follower was determined by calculation. And test results showed that transmission of forced sowing and forced opening for corn direct seeding machine was stable, which can complete picking and seeding corn, and duckbills when metering did not clip soil, and film hole was small, and there were no problem that duckbills pick film, tear film, etc. The hole rate of corn insert plot hill-drop planter was 1.8%, cavity and seed number of qualified rate was 95.3% and planting under film depth pass rate was 88.1%, thus the design of strong seeding corn-strong opening duckbill of insert plot hill-drop planter met the design requirements and agronomic techniques of corn planting.