竹材去隔机刀具摆动机构的分析研究

Analysis research of the swing mechanism of bamboo separator tool

针对竹材去隔机刀具摆动机构,阐述了刀具摆动机构的组成及工作原理,根据矢量方程构造了刀具摆动机构摆角与时间的数学模型,对去隔过程进行仿真分析。设定刀具摆动机构曲柄的转速为π/4 rad/s,对去隔机刀具摆动机构进行仿真,仿真结果表明:刀具中心摆动角度的变化范围为0°~90°,可对圆心角为90°的竹材进行去隔操作。采用Adams对竹材去隔机刀具摆动机构建立虚拟样机,同样以π/4 rad/s的曲柄转速对竹材去隔机去隔过程进行仿真。结果表明:刀具中心摆动范围与计算值相同,验证了数学模型的准确性,同时对连杆两端受力进行计算,得到连杆两端受力随时间变化的曲线,连杆受力发生周期性突变,最大受力约为190N。将受力情况以表格的形式导入Ansys APDL对连杆进行瞬态动力学分析,仿真结果表明:连杆内应力约为1.3MPa,远远小于材料的屈服极限,保证了去隔机工作的安全性,验证了设计的合理性。同时,结果表明:在对竹材去隔的过程中应力会发生突变,可能产生振动,去隔机应避免在其固有频率下工作。

Owing to the enlarged concerns of global warming,interest of utilizing bamboo has been greatly increased because bamboo can be a good alternative to wood in its various applications,which would decelerate the destruction of forests.However,because of the hollow outer circle of bamboo,it is difficult to be processed and utilized.As the rise of labor cost,the processing cost of bamboo also rises.Therefore,it is of great significance to accelerate the research and development of bamboo processing machinery.Aiming at designing the most efficient bamboo separator tool,the composition and working principle of the tool swing mechanism were elaborated.Based on the vector equation,the mathematical model of the swing angle and time of the tool swing mechanism was constructed,and the process of separating was simulated and analyzed.The crank speed of the tool swing mechanism was set to π/4 rad/s,and the tool swing mechanism of the separator was simulated.The simulation results showed that the center swing angle of the tool varied from 0° to 90°,and the bamboo with 90°of the center angle could be de-spaced.The virtual prototype of bamboo separator tool swing was built by Adams,and the process of bamboo separator separating was simulated by the crank speed ofπ/4 rad/s.The results showed that the swing range of the tool center was the same as the calculated value,which verified the accuracy of the mathematical model.At the same time,the force on the two ends of the connecting rod was calculated.The curves of the force on the two ends of the connecting rod changed with time were obtained.The maximum force on the connecting rod was about 190 N,and the force changed periodically.The force on the connecting rod was imported into Ansys APDL in the form of tables for the transient dynamic analysis of the connecting rod.The simulation results showed that the internal stress of the connecting rod was about 1.3 MPa,which was much less than the yield limit of the material.It ensured the safety of the separator and verified the rationality of the design.At the same time,the results showed that the stress would change abruptly in the process of removing bamboo,which may cause vibration.The separator should avoid working at its natural frequency.