The Advanced Handbrake Actuator System

State-of-the-art freight car handbrakes are manpower intensive. Setting and releasing handbrakes expose operators to safety hazards and the potential for human error exposes train operations for possible time delays, mild to severe maintenance issues and ultimately the potential for major rail accidents. In response to the need to reduce the hazard associated with freight car handbrakes, UTD has developed the Advanced Handbrake Actuator System (AHAS), a fail-safe powered handbrake device, accessible from ground level on either side of the car. The AHAS concept was developed, manufactured and demonstrated under sponsorship of the Federal Railroad Administration (FRA) Small Business Innovation Research (SBIR) program. The system is designed to replace existing handbrake wheels and provide significant improvements by offering new ways of applying or releasing the brake. Remote electronic signal, car mounted hand levered pneumatic valve, and a manual hand crank mechanism, requiring significantly less effort than that required by the state-of-the-art handbrake wheel, constitute three methods of actuation. The AHAS is comprised of a compression coil spring arranged to apply tension to the handbrake chain as its default condition. Two release systems are available. The first uses an air cylinder actuator connected in series with the spring and chain. Applying air pressure by remote or local command will compress the spring and release the handbrake. The spring may also be compressed to release the handbrake by a hand crank mechanism, accessible from ground level on either side of the car. The AHAS is equipped with a dedicated air reservoir charged with compressed air prior to departure via the train’s brake pipe. The AHAS was successfully field tested on a freight car in regular service over a period of three months and was found to be user friendly and safe, logging over 120 successful operations.