HIGH PRECISION DUPLEX BEARING WITH THERMAL OFF-LOAD DEVICE FOR THE NIRSPEC WHEEL SUPPORT MECHANISMS

Austrian Aerospace has the privilege to develop the wheel support mechanisms for the Filter Wheel and the Grating Wheel of the Near Infrared Spectrograph (NIRSpec) Instrument of the James Webb Space Telescope (JWST). One of the key components of the wheel support mechanisms are the bearings which shall - have highest accuracy, - have low friction torque during operation, - withstand considerable launch loads and - withstand cryogenic operating temperatures of 30K. The chosen bearing is a custom-made hard preloaded flanged duplex ball bearing in back to back configuration with a novel thermal off-load device.