Disc springs provide reliable braking backup

The amount of friction between each set of plates controls the deceleration of the vehicle. However, without an additional fail safe system, this design alone has limited reliability. If a hydraulic seal is compromised, or the hydraulic cylinder loses pressure for any reason, the brakes fail. To combat this problem, Spirol has developed a mechanical back-up design using disc springs. Under normal circumstances, the hydraulic system holds a constant pressure on disc springs stacked in series. If pressure fails to be maintained, the stack decompresses to actuate the braking mechanism. The reliability of this safety system is dependent on the consistent performance of disc springs. The disc springs have a high capacity to consistently store releasable mechanical energy. Their conical design makes their spring characteristics and performance more predictable than traditional compression springs. They are also capable of providing more force in less space than a compression spring or wave spring. They also allow fatigue endurance to be predicted. Stress analysis enables the minimum cycle life of singularly or stacked disc springs to be calculated as a part of the application's design.