中文摘要：

为满足青藏高原等牧区青草制辫机械化需求,参考赛络纺的工作原理,设计了一种青草制辫成型装置,实现草辫的加捻和合股。通过力学分析,得知青草制辫成型与草辫轴向移动速度、加捻滚筒旋转速度、加捻滚筒半径以及喂入量有关,并分析出稳定草辫的最终捻度和捻回角,与加捻滚筒转速及牵引辊线速度有关,与加捻时间和加捻区的长度无关。结合实际,提出将草辫承受的最大拉力作为评价草辫紧实度考核指标的一种方法,并对草辫进行了受力分析,得出草辫所能承受的最大拉力与捻回角成正相关。样机试验结果表明,成型机生产率为427 kg/h,工作功率为0.428 k W,成型草辫堆积密度为143.3 kg/m-3,成型草辫所能承受的最大拉力为300-350 N,试验结果满足实际作业要求。

英文摘要：

In order to meet the requirement of the grass braid mechanization technology in the pasturing area such as the Qingzang Plateau,a grass braid forming device was designed with the function of twisting and plying referring to the principle of Siro-spinning. The mechanical analysis showed that grass braid forming process was affected by axial movement speed,rotating speed of twisting roller,radius of twisting roller and feed quantity. The final twist and twist angle of grass braid were only relevant to the rotational speed of twisting roller and the linear velocity of pulling rollers,but had nothing to do with the spinning time and length of twisting zone. As a new method,the maximum tension force that grass braid could bear was taken as assessment index of grass braid strength. The prototype experiment was carried out with oat straw with the moisture content of 61. 05%. It showed that the productivity of the forming device was 427 kg/h,the working power was 0. 428 k W,and the bulk density of formed grass braid was 143. 3 kg/m-3,respectively,which met the design requirements of grass braid forming device. The results of tension tests showed that the maximum tension force of the grass braid was positively correlated with the twist angle,and the maximum force reached 300 - 350 N when the displacement was equal to half of the length of grass. The fracture of grass braid was due to the slip between two bunches of grass,which had nothing to do with grass fracture. This method and experiment provided theoretical support for grass braid forming technology.