川麦冬往复切割式剪果装置设计与仿真试验

Design and Simulation Experiments of Reciprocating Cutting Tuber Removal Device for Ophiopogon japonicus

麦冬为我国大宗中药材品种,道地产区为四川和浙江,地下部分的块根为入药部位。本文针对麦冬块根采后人工脱果劳动强度大,缺乏成熟机械化脱果装置等问题,设计了一款川麦冬剪果装置。该装置采用两组阶梯式的往复切割器、输送夹持带、限果导须板和机架结构。结合麦冬剪果农艺要求和植株物理参数测量计算,确定了整体结构尺寸、限果导须板间隙、输送速度、切割间距、往复行程等参数。基于ADAMS软件对麦冬与脱果刀具之间进行了刚柔耦合仿真分析,以刀刃与麦冬植株接触力大于峰值切割力为条件,模拟切割效果;利用ADAMS/view中Flex模块对麦冬植株进行柔性化处理,分析在接触碰撞过程中两者接触力与麦冬植株形变的变化规律。选取切割速度、切割倾角、刀具构型三因素进行三水平正交试验,结果表明,影响切断的因素主次顺序为切割倾角、切割速度、刀具构型;切割速度与刀刃类型呈显著相关关系;当进行高速切割时,直齿型刀具所产生的峰值切割力大于其他两种刀具构型。综合考虑切割稳定可靠性、切割力和刀具构型最简化原则,得到优化工作参数为:切割速度0.41 m/s、切割倾角0.3°、刀具构型为三角光刃型。经仿真验证,该装置结构参数合理,满足麦冬脱果技术要求,可为麦冬脱果机械装置的优化设计提供理论和试验依据。

Ophiopogon japonicus is a major variety of traditional Chinese medicinal herbs,which mainly cultivated in Sichuan Province and Zhejiang Province,and the medicinal part of it is the tuberous root normally barrier underground.Focusing on the labor intensive process of manually removing the tuberous root from Ophiopogon japonicus,as well as the lack of mature mechanical tuberous root removal devices,a tuberous root removal device was specifically designed for Ophiopogon japonicus from Sichuan Province.The device utilized two sets of step type reciprocating cutters,a set of conveying clamping belt,a caliper,and a rack structure.By considering the requirements of the tuberous root of the Ophiopogon japonicus harvesting and measuring the plants’physical parameters,parameters such as overall structure dimensions,caliper interstices,conveying speed,cutting intervals and reciprocating stroke can be determined.The rigid-fliexible coupling simulation analysis between the Ophiopogon japonicus and the tuberous root removal tool was conducted by using ADAMS software.The cutting effect was simulated under the condition of the contact force between the cutting edge and the Ophiopogon japonicus plants exceeded the peak cutting force.The Felx module in ADAMS/view was used to apply flexible treatment to the Ophiopogon japonicus plants,and the changing rules in contact force and plant deformation during the contact collision process was analyzed.Choosing cutting speed,cutting inclination angle and cutting tool configuration as three factors to design a three level orthogonal test.The order of importance for factors affecting cutting effects was as follows:cutting inclination angle,cutting speed,and cutting tool configuration.Cutting speed was significantly correlated with the type of cutting tools.When proceeding high-speed cutting,the peak cutting force generated by the straight-tooth blade tool was greater than that of the other two configurations.Considering the principle of cutting stability reliability,cutting force and tool configuration minimization comprehensively,the optimized solution was carried out:the optimal working parameters was determined as cutting speed of 0.41 m/s,cutting inclination angle of 0.3°and a cutting tool configuration of a triangular smooth-edge blade.Verified by simulation,this device had rational structure parameter and met the technical requirements for the harvest of Ophiopogon japonicus tuber,providing a theoretical and experimental references for the further optimization design of mechanical devices.