Instability in the Hand-Brake Performance of Cars and Vans

Abstract

Drum brakes of leading and trailing shoe design are commonly used on the rear axles of cars and vans, and their handbrake actuation is frequently accomplished by means of a strut between the two shoes. Occasional instability in the handbrake performance, which may culminate in brake lock and consequent shock loading of brake components, has been investigated experimentally and analytically. Lining friction and contact pattern, brake geometry and design are all considered as influencing factors and some unusual mechanisms of brake operation, which may occur under certain conditions, are explained as causes of the instability.