Implementation of a Non-Metallic Barrier in an Electric Motor

Electric motors that run in pure oxygen must be sealed, or “canned,” for safety reasons to prevent the oxygen from entering into the electrical portion of the motor. The current canning process involves designing a metallic barrier around the rotor to provide the separation. This metallic barrier reduces the motor efficiency as speed is increased. In higher-speed electric motors, efficiency is greatly improved if a very thin, non-metallic barrier can be utilized. The barrier thickness needs to be approximately 0.025-in. (≈0.6-mm) thick and can be made of a brittle material such as glass. The motors, however, designed for space applications are typically subject to high-vibration environments.