Articulated windshield wiper blade assembly

Abstract

An articulated twin spline windshield wiper blade assembly includes an elongated, resilient, thin-walled polymeric female spline of relatively high durometer having a generally planar backbone, and two opposing arcuate spline legs which extend downwardly from the backbone and cooperate with the backbone to define a cylindrical spline channel. The wiper blade assembly further includes an elastomeric male spline having a cylindrical body portion rotatably journaled within the spline channel of the female spline. The male spline further includes a neck portion depending from the body portion, and a wiping portion depending from the neck portion. The wiping portion includes opposing wiping edges which are alternately engagable with a surface to be wiped upon rotation of the male spline within the spline channel. The specific selections of material and dimensions of the male and female splines provide a conflicting combination of the proper amount of flexibility of the female spline to allow the spline to properly conform to the curved surface of the windshield, proper rigidity of the backbone of the wiper to support proper engagement forces with the windshield, proper flexibility of the female spline legs relative to the backbone to prevent the legs from squeezing the male spline too tightly during rotation, and the removal of excess flashing material from the outer surfaces of the male spline. To further reduce friction and resistance to rotation, the cylindrical body portion of the male spline is truncated at its uppermost edge.