喷气织机打纬机构用共轭凸轮设计

Design of Conjugating Cam Used in Beating-up Mechanism of Air-jet Loom

为了提升喷气织机织造性能,分析现有四连杆打纬机构、六连杆打纬机构、共轭凸轮打纬机构存在的问题,提出一种能满足不同幅宽、不同车速喷气织机需求的共轭凸轮打纬机构解决方案;介绍共轭凸轮外形及运动曲线,对比其与四连杆、六连杆的位移、速度、加速度、急跳(跃度)的曲线变化,分析后死心完全静止的大静止角凸轮和后死心主动摆动的大静止角凸轮存在的不足,参照连杆打纬设计出仿八连杆共轭凸轮打纬机构。指出:共轭凸轮打纬机构曲线流畅顺滑、无突变情况,可用于高速窄幅喷气织机;仿八连杆共轭凸轮打纬机构打纬,在后死心位置有约200°的相对静止角度,且织机运转1圈仅出现2次升降变化,加速度及跃度曲线顺滑、接近连杆机构打纬曲线,满足高速宽幅喷气织机更多引纬时间和更大打纬力的织造需求。

In order to improve the weaving performance of air-jet loom,the existing problems of four-link beating-up mechanism,six-link beating-up mechanism and conjugating cam beating-up mechanism are analyzed,and a solution for conjugating cam beating-up mechanism which can meet the needs of different width and speed of air-jet loom is proposed.The shape and motion curve of conjugating cam are introduced,and its curve changes of displacement,velocity,acceleration and sharp jump(leap)are compared with those of four-link and six-link.Based on the analysis of the shortcomings of the large static angle cam with the rear dead center completely stationary and the large static angle cam with the active swing of the rear dead center,the imitation eight-link conjugating cam beating-up mechanism is designed.It is pointed out that the curve of the conjugating cam beating-up mechanism is smooth and without abrupt change,which can be used in high-speed narrow air-jet loom.With a relative static angle of about 200°at the rear dead center of the imitation eight-link conjugating cam beating-up mechanism,the acceleration and jump curve are smooth and close to the beating-up curve of the linkage mechanism,which can meet the weaving needs of high speed and wide width air-jet loom with more weft insertion time and greater beating-up force.