Brake disc for cycle disc brake systems has flat surface recesses on outer friction ring each in circular arc form inclined in rotary direction of disc and specially configured for better braking action

摘要

The outer friction ring (3) of the brake disc has flat surface recesses whose rear defining edges, seen in the rotary direction of the disc are in a circular arc with the midpoints of the circles on which these edges lie being in front of the edges . The edges are inclined in the rotary direction of the disc so that a straight line drawn from the midpoint of the disc through the point closest to the midpoint on the boundary edge contacts this boundary edge only at this point.