摆杆极位直到三阶停歇的斜交轴型空间六杆机构设计

Design on rocker doing unto three-ordered intermission on limit positions of spatial six-bar mechanism with oblique intersection axes

在传统的机构设计理论中高阶停歇的空间传动机构设计只能采用迭代方法,既存在着初值的选择与多解的识别问题、也存在顺序的判断问题.现在采用复合函数与组合机构相对应的构造方法.若复合函数中两个基本函数在同一位置的一阶导数同时为零,则复合函数的一至三阶导数在对应位置为零.设两个基本机构的传动函数对应两个基本函数的零点,则该组合机构的输出构件在对应位置作直到三阶的停歇.此原理所进行的设计为非迭代设计,不仅设计简单,而且没有理论误差,开创了一种构造式的高阶停歇空间传动机构的设计原理.以输出摆杆在极限位置作直到三阶停歇的一类斜交轴型空间六杆传动机构为例,展示了设计过程与这一类机构的传动特征.

High order intermittent spatial transmission mechanism designed in traditional mechanism design theory has to adopt an iterative method, it exists not only the problems of initial value selected and many solutions identified but also the problem of sequence judged. Now a construction method is used, it makes a compound function corresponding to a combination mechanism. One to three order differentials of a compound function are zero if one order differentials of two basic functions are zero at the same moment. Suppose the transmission functions of two basic mechanisms are corresponding to zero points of the two basic functions, then output member of the spatial combination mechanism will do unto three ordered inter- mittence at corresponding position. This principle is a non-iterative design, this design not only is simpler, but also is without theoretical error. This initiates a kind of structural design principle on high order interrnittent spatial transmission mechanism. An output rocker doing unto three-ordered intermission on limit positions of spatial six-bar transmission mechanism with oblique intersection axes is used as a case, in order to show design process and transmission characteristic of the mechanism.