Patent ID: 8550218

Claim:
A brake actuator for a progressive cavity pump, the progressive cavity pump having a first motor producing first output for rotating a drive shaft and having a rotatably-actuated brake mechanism for stopping rotation of the drive shaft, the brake actuator comprising: a second motor producing second output independent of the first output of the first motor for rotating the drive shaft; a coupling connecting the second output of the second motor to the rotatably-actuated brake mechanism of the progressive cavity pump to control the rotation of the drive shaft independent of the first output of the first motor; and a controller operatively coupled to the second motor and monitoring rotational speed of the drive shaft of the progressive cavity pump, the controller determining an amount of the second output of the second motor based on the rotational speed of the drive shaft of the progressive cavity pump and controlling operation of the second motor to produce the determined amount of the second output to apply to the brake mechanism.