Synthesis of 4-Bar Linkages Adjustable for Several Approximate Straight-Line Motions of a Coupler Point

Abstract

A design technique which makes use of the unique inflection circles that result when the instant center (pole) falls at a fixed pivot or at a link pivot is developed to synthesize a 4-bar linkage which has a point or points on its coupler plane which trace two straight-line motions of specified angular displacements for two adjustments of a “fixed” pivot. When combined with an adaptation of the Euler-Savary equation, this technique can be used to synthesize a 4-bar linkage having a coupler point which traces three straight-line motions for three specified adjustments of a fixed pivot.