基于开口工艺要求的多臂机机构参数分析

Analysis on Mechanism Parameters of Dobby Based on Requirement of Opening Process

为了探寻多臂机机构参数与开口工艺要求的关系,采用基本原理分析、机构运动学分析等方法,对法国Staubli公司的2658型多臂机的提综机构进行分析。研究结果表明：偏心盘控制单元应设计成无急回特性的曲柄摇杆机构,相邻综框对应的曲柄相位差应为180°,确保了综平位置和综平时刻的一致性,且综平时刻偏心方向与提综臂方向平行,但是上下开口极限动程无法一致,下开口极限动程大于上开口极限动程;综平时刻,综框调节机构的提综臂圆弧中心应在送杆和大刀片的铰接点;通过合理设计综框机架与大刀片中心的相对位置,可以确保上下开口动程的一致性;共轭凸轮旋转变速机构的引入增加了开口的静止时期,延长了纬纱通过梭口的时间。

In order to explore the relationship between dobby mechanism parameters and the opening process requirements,kinematics analysis and other methods were used to analyze the heald lifting mechanism of French Staubli Company＇s type 2658 dobby.The research result shows that the eccentric disc control unit should be designed to be the crank rocker mechanism without quick-return characteristic and the crank phase difference corresponding to adjacent heald frames shall be 180°,which ensures the consistency between flat heald position and flat heald moment,and at the moment of flat heald,the eccentric direction parallels lifting heald arm.But the limit strokes of upper and lower openings cannot be consistent,the lower limit stroke is bigger than the upper one.At the moment of flat heald,the arc center of lifting heald arm of heald frame regulating mechanism should at the hinged point between feed bar and big blade.Properly designing the relative position between heald frame rack and the center of big blade can ensure the consistency between the strokes of upper and lower openings.The introduction of conjugate cam rotating variable speed mechanism increases the rest period of opening,and prolongs the time of weft yarns going through the shed.