Safety brake for vehicle transmission - has centrifugal limiter on engine drive shaft to prevent excessive speed on overrun

摘要

A simple protective brake (10) fitted to the output drive shaft of an engine to protect the engine on overrun. The brake comprises a centrifugal design with increasing effect with speed and is controlled by a fail-safe sensor (11) and acts progressively when the vehicle runs downhill. The brake sensor can monitor torque, with the brake acting only if the torque transfer is in the reverse direction ie towards the engine. The engine can be used for engine braking without danger of overloading and the point at which the brake begins to act is well below the safe shaft speed of the engine. The system is esp. useful in engine driven hydraulic transmissions, without requiring separate hydraulic brakes.