一类空间 4R-C 过约束条件的探讨及其在纺织机械中的应用

本文应用封闭环矩阵形式方程论证了一类空间4R-C 五杆过约束机构。进一步研究表明:在这类过约束机构中,当两组平行轴相互垂直交叉时得到下列新结论:1.对由 R、C 组成的这类机构,C 副安置在哪一个轴上,应满足一定的限制条件,否则就不能实现主、从动轴间的相对空间运动。2.对由 H、C 组成的这类机构,在特定的螺矩关系下,C 副的任意安置仍有可能;即对 H 副成立的结论不能无条件地推广到 R 副上。应用上述结论,作者设计了空间 RRCRR 机构(这类过约束机构的一种),应用于织机多臂提综装置,经试验运转效果良好。

AN ANALYSIS OF A SORT OF SPATIAL 4R-C OVERCONSTRAINED CONDITIONS AND THEIR APPLICATION IN TEXTILE MACHINERY

This paper expounds and proves a sort of spatial 4R-G five-bar overconstrained mechanisms by working out the closure matrix equation.Two particular results are obtained as follows when the two sets of parallel axes are perpendicular to each other. 1.For the mechanism composed of R-pairs and C-pair,the kinematic conditions must be satisfied for the locating of C-pair,otherwise,there can't be any spatial motions,either. 2.For the mechanism composed of H-pairs and C-pair,the position of C-pair can still be arbitrarily located according to the particular relations of the pitch of H-pair.Nevertheless,the conclusions available for H-pair can't be applied to R- pair at any time. Applying the results above,the authors of the paper have designed an RRCRR spatial mechanism (one kind of such overconstrained mechanisms) that can be used in hardness-lifting device of dobby looms.The testing results prove to be very satisfactory.