机械

速度瞬心法是分析机构速度的一种既直观又简便的方法。如何确定瞬心的位置,尤其是确定复杂机构的速度瞬心位置比较繁琐。通过对机构速度瞬心的研究,在速度瞬心定义和三心定理的基础上,提出了瞬心链的概念及构筑瞬心链的新方法。建立了机构速度瞬心多边形,找出非直接接触构件的所有瞬心链路,根据瞬心多边形中两构件间路程长短寻找最短瞬心链路,利用三心定理确定两构件的瞬心位置,给出了确定复杂机构中相隔两个及以上构件间的非直接接触构件的速度瞬心位置的步骤。利用瞬心链可以将复杂机构的速度瞬心位置确定的复杂问题转化为简单的查找瞬心链的程式化过程,为复杂机构速度瞬心位置的确定提供了方便可行的方法。

The velocity instantaneous center method is an audio-visual and simple way to be used to analyze mechanic motion.How to locate the instantaneous center of velocity of complex mechanism is very difficult problem.The concept of instantaneous center chain is put forward,and a new method for establishing instantaneous center chain of complex planar linkages is studied by definition of instantaneous center and the Aronhold-kennedy theorem.The polygon of instantaneous center is set up to finding all instantaneous center chains between non-contact linkages.A new procedure to find all instant centers and the shortest path leading to any instant center of a complex mechanism using instantaneous center polygon has been explained.Using instantaneous center chain,the problem of finding instant center positions of a complex mechanism can be solved through simple finding the shortest instantaneous center path,the method is simple and practical.