割刀自适应的采茶装置设计与分析

Design and analysis of tea-plucking device with adaptive adjustment of cutter

针对现有采茶机作业时老、嫩茶叶一刀切、嫩芽切碎及茶树机械损伤等问题,设计一种割刀自适应调节的采茶装置。根据坡地茶园地形参数和茶茎力学特性,确定采茶装置的机械及结构参数,使得割刀自适应采茶;通过对采茶装置运动学和动力学分析,建立割刀水平调节过程运动学方程和割刀切入角调节过程动力学方程,确定影响割刀运动的主要因素为:茶茎对割刀的反作用力、曲柄长度、摇杆长度和铰链安装长度;利用力矩平衡原理,得到割刀纵向偏转的充要条件,确定茶茎反作用力范围为0~55.42 N;采用Adams开展对割刀水平调节过程仿真分析,确定最优曲柄长度、摇杆长度和铰链安装长度分别为330 mm、200 mm和500 mm。

Aiming at the problems of indiscriminate cutting of old and young tea leaves,crushing of tender buds,and mechanical damage to tea trees in the existing tea pickers,a tea-plucking device with automatic cutter adjustment was designed in this paper.Based on the terrain parameters of sloped tea plantations and the mechanical properties of tea stems,the mechanical and structural parameters of the harvesting device were determined,enabling flexible tea harvesting by the cutter.Through kinematic and dynamic analysis of the plucking device,the kinematic equations for horizontal cutter adjustment and dynamic equations for cutter cutting angle adjustment were established,identifying the main factors influencing cutter motion as the counterforce of the tea stem on the cutter,crank length,rocker arm length,and hinge mounting length.By using torque equilibrium principles,the necessary and sufficient conditions for longitudinal cutter deflection were obtained,determining the counterforce range as 0-55.42 N.Adams simulations of the horizontal cutter adjustment process were utilized to identify optimum crank length,rocker arm length,and hinge mounting length as 330 mm,200 mm and 500 mm,respectively.