Patent ID: 8328165

Claim:
A hoist system comprising a drum assembly, a drum brake, a motor assembly, a motor brake, a first encoder, a second encoder, and a controller module, wherein: the motor assembly is structured, connected, programmed and/or located to drive the drum assembly to rotate; the second encoder is connected, structured, connected and/or located to detect rotational velocity of a portion of the drum assembly and to output a second encoder output signal corresponding to the drum assembly rotational velocity; the first encoder is connected, structured, programmed and/or located to detect rotation of a portion of the motor assembly and to output a first encoder output signal corresponding to the motor assembly rotational velocity; the controller module is structured, connected and/or programmed to receive the first encoder output signal and the second encoder output signal, to compare the first encoder output signal and the second encoder output signal, to determine whether an overspeed condition exists in the hoist system based on the comparison, and to output a motor brake control signal and a drum brake control signal upon determination of an overspeed condition; the motor brake is structured, connected, located and/or programmed to receive a motor brake control signal from the controller module and to brake the rotation of the motor upon receipt of the motor brake control signal; and the drum brake is structured, connected, located and/or programmed to receive a drum brake control signal from the controller module and to brake the rotation of the drum assembly upon receipt of the drum brake control signal.