整排取苗间隔放苗移栽机设计与试验

Design and Experiment of Full-row-pick-up and Single-dropping Seedling Transplanter

为提高穴盘苗移栽机的自动化程度和工作效率,结合井关PVHR2型旋转托杯式半自动移栽机,设计了一种可实现整排取苗间隔放苗的自动移栽机。其中,取苗末端执行器用于实现钵苗的整排夹取和间隔投放,旋转升降机构用于协助取苗末端执行器完成携苗上升、正转90°至投苗位置、反转90°回取苗位置及下降取苗动作。基于整排取苗间隔放苗工作原理,对取苗爪驱动凸轮的外形轮廓进行设计,以实现取苗爪的先后开合;结合取苗机构组成和作业时序要求,对整排取苗部件与穴盘输送机构的运动循环过程和时序分配进行分析,进而对各凸轮机构的时序进行控制,以实现机构间的运动协调,完成自动移栽作业。以28 d的72孔穴盘黄瓜苗为对象,进行样机试验,试验结果表明:整个取苗机构的时序分配合理,运动协调可靠,可实现整排取苗间隔放苗的作业要求;在取苗速率为3 600株/h、夹苗深度为27 mm、取苗夹角为10°时,取苗效果最佳,成功率达95%。

To improve the automation and efficiency of plug seedling transplanter,a full-row-pick-up and single-dropping seedling transplanter was designed based on the type-PVHR2 semi-automatic transplanter with rotary seedling-received cup device.The seedling pick-up end-effector system performed the removal of total number of seedlings in a row and dropped them individually into their cups.The rotary-lifting mechanism was used to help the end-effector to move down to pick the seedlings from the tray upwards,rotate at 90° to drop the seedlings into the cups,and reverse at 90° to the upside of tray.With the principle of fully picking the row seedlings and dropping them one-by-one in mind,seedling pick-up unit driven cam contours were designed to open and close the pick-up units.Based on the transplanting requirements,motion matching and timing control of the mechanism and the cams were carried out to ensure proper coordination in the transplanter.Automatic transplanting experiments for the 72-hole plug cucumber seedlings with the age of 28 d showed that the designed mechanism was reliable with a success pick-up rate of 95% at pick-up speed of 3 600 seedlings/h,pick-up embedded depth of 27 mm,and pick-up angle of 10°.