Contributions to the synthesis of the windshield wiper mechanism with one rocker-slider blade

Abstract

The paper deals with synthesis of the windshield wiper mechanism with one rocker-slider blade. Starting from the kinematic scheme of the constructive model designed by Mercedes-Benz motor vehicle company, a structure analysis on this complex mechanism consisting of three kinematic chains, of which two are articulated bar mechanisms and one is planetary mechanism, has been accomplished. The novelty of this paper consists in the presentation of an optimum synthesis method of the planar bar mechanism in two variants for the wiper blade driving. The first variant is a planar 4-bar mechanism type crank-rocker where the cosines theorem has been applied in order to obtain the lengths of the coupler and the crank. The second analyzed variant is a bi-contour linkage consisting of two 4-bar mechanisms linked in series. Further, the calculation of the planetary gear angular velocity on the complex mechanism with dyadic kinematic chains has been achieved. In order to do this, the immobilization of the planetary carrier method has been applied. Finally, the geometry of the driven linkage of the wiper mechanism type crank-slider which has two mobilities has been studied. A vector equation has been written in order to obtain the length of the variable blade.