Lightweight design of a torque plate of Z-cam drum brake for heavy duty vehicles

Reducing vehicle weight without compromising performance becomes an area which is important to improve fuel economy and reduce vehicle emissions. The possibility of reducing unsprung mass in a vehicle has led to many investigations of weight optimization studies of axle and wheel-end components. Therefore, structural design of a torque plate, which is one of the main parts of a Z-cam drum brake used in heavy-duty vehicles, is carried out by using topology optimization and finite element analyses. Firstly, finite element analysis of the original torque plate is conducted to determine critical stress levels and locations. Secondly, topology optimization is carried out on the original torque plate for specified loading conditions. Taking redundant volume and manufacturability constraints into account a new torque plate design is composed. Finally, finite element analysis is repeated to verify the final design. A significant decrease in stress level is accompanied by considerable reduction in casting and machined part masses by 11.9% and 12.2% respectively.