曲柄齿条滑块极位三阶停歇的七杆机构设计

Design of Seven-bar Mechanism of Slider at limit Positions Doing unto Three Orders Intermission Based on Crank-rack

高阶停歇机构的设计理论是机构设计理论中的重要分支之一。数学分析表明,复合函数中两个相关函数在同一时刻的一阶导数等于零,导致复合函数的一至三阶导数在对应时刻为零,此原理开创了高阶停歇机构设计的新方法。研究表明,该数学原理对应几十种从动件在极限位置作直到三阶停歇的平面或空间机构。本文仅介绍了一种基于曲柄齿条的滑块在单或双极限位置具有直到三阶停歇的平面七杆机构的设计,研究了它的高阶传动特征。该种机构结构简单,容易设计,传动角大。

Design theory of high order intermittent mechanisms is an important branch of mechanism design.Mathematical analysis manifests that that one order differential of two correlative functions in a compound function at same moment is zero leads to one to three order differentials of the compound function at corresponding moment to be zero.This a principle sets up a new method on high order intermittent mechanisms.Research indicates that this a mathematical principle corresponds to tens kinds of planar or spatial mechanisms which driven members at limit position(s) do unto three orders intermission.For this reason,it is only introduced that a type of seven-bar mechanisms of the slider at limit position(s) does unto three orders intermission based on crank-rack and its design,its transmission characteristics are studied.The mechanism has the simpler structure and its design is easier and transmission angle is larger.