Abstract: A shaft or shafts are connected to a rotor core of a dynamoelectric machine without the need for a central hole in the laminations of the core. The shaft is connected to the core by attaching the shaft to a rotor end plate (or forming the shaft and the end plate as a single unit) and connecting the end plate to the core at a distance away from the axis of the core. The rotor may have similar end plates at both ends, the end plates attached to each other and to the core by through studs or bolts that pass through holes in the laminations. The holes and the studs or bolts are evenly circumferentially spaced at a distance from the axis. The through studs or bolts are secured at either end, clamping the end plates with the rotor core between them. The rotor end plate provides support to the rotor end ring that forms part of the squirrel cage of the rotor core. The end plate includes a lip or other portion which restrains movement of the end ring in lateral and/or axial direction(s) as the rotor rotates.

Abstract: A diagnostic system includes a vibration sensor mounted on a machine which has vibration-generating components having different vibration characteristics with respect to a common sensor. The vibration sensor measures vibrations and sends vibration signals to a diagnostic module for evaluation of the signals. The diagnostic module has software for processing the vibration signals. From a known natural frequency of a vibration-generating component, the diagnostic module measures the amplitude of the vibration signal at more than one harmonic frequency of the known natural frequency and compares the amplitudes to amplitudes at adjacent harmonic frequencies.

Abstract: A method and apparatus for real-time electric motor diagnostics and condition monitoring. While the motor is energized, dynamic operating parameters are determined and a notification signed is generated if predetermined criterion are satisfied. The diagnostic apparatus is integrated with the motor and includes a set of sensors, a processing unit, a memory and an output interface for communicating alarms, warnings and calculated operating parameter values or the like to a display device and to an external supervisor having wireless paging capability to alert a remote operator or maintenance personnel. In a normal operating mode, the processing unit calculates a general class of derived motor operating parameters such as over-temperature, over-voltage, over-current, excessive vibration, and phase imbalance.