Analysis of the effect of the wedged type brake caliper piston on brake drag

Reducing brake drag has always been one of the most important goals among brake system engineers and its importance has never been higher due to the historic rise in global fuel economy and carbon emission standards. Although many studies have been done with regard to the improvement of brake drag, previous papers have focused mainly on studying the optimization of traditionally well-known factors such as geometry of the piston seal groove where the piston seal is to be located, piston materials, properties of the piston seal, and so forth. In contrast, only few papers deal with the entire mechanism of the piston roll-back. The present work tries to change the shape of the piston(wedged type) to differentiate the mechanism of the piston roll-back from the conventional method and attempts to illuminate the interaction between wedged type brake caliper piston and piston seal. Data from multi sources including several different dynamic drag tests and CAE analysis are presented and discussed in order to understand better for the effects of wedged type piston on brake drag.