Analyses of thrust bearings in scroll compressors considering keyways

This work is an attempt to calculate the lubricating characteristics of thrust bearings in scroll compressors, which have non-circular shapes due to the keyways cut for the Oldhamʹs coupling. The outer shapes of these bearings are not circular because the keyways intrude the bearing boundaries. A boundary fitted coordinate technique for hydrodynamic lubrication is modified to handle this non-circularity. The pressure distributions, resultant forces and moments are calculated, which are in equilibrium to the typical conditions generated in the compressing processes. The changes of nominal clearance and tilting angles are obtained during one cycle under the assumption of rigid-body motions.