Patent ID: 7849979

Claim:
A brake drum, comprising: (a) an annular disk-shaped endwall adapted to be connected to a vehicle wheel for rotation about an axis, the endwall including a radially outermost portion, (b) a sidewall extending generally parallel to the rotational axis having (1) an inner surface that extends from a first open end to a second end disposed toward the endwall with the inner surface defining a rub track section, and (2) a relatively smooth outer surface that is concave having a maximum cross sectional thickness disposed at or adjacent the second end and a minimum cross sectional thickness disposed a distance axially therefrom, (c) a generally arcuate and concave transition portion extending from the endwall to the second end of the sidewall interconnecting the endwall and the sidewall, the transition portion connecting to an end surface of the second end of the sidewall, the end surface of the second end of the sidewall facing toward the endwall and defining a largest diameter portion of the brake drum, the transition portion further comprising a first portion that extends radially inward from the sidewall toward a remainder of the transition portion, the first portion having an outwardly facing surface that is coplanar with and continuously connects to the end surface of the second end of the sidewall, and wherein the endwall, sidewall, and the transition portion define a brake drum formed in one unitary piece.