Uncontrolled Overspeed

Abstract

The major part of the design and specification of equipment for the arrest or prevention of overspeed, particularly the safety gear/overspeed governor combination, concerns itself with the performance when carrying rated load, or, in the event of upward overspeed, zero load in the car. In particular, specification is concerned with performance of safety equipment in the face of suspension failure, however unlikely that might be. This paper sets out to investigate the performance of overspeed protection when there is a partial load in the car, whether with a failed suspension or not, and to discuss the opportunities in this respect provided by the introduction of the so-called rope brake.