US Patent 10451104 Gas bearings

A gas bearing system has at least one gas bearing (30, 32, 34) with a moving part and a static part and which can be operated in both aero-dynamic and aero-static modes. The system has a source (36) of pressurized gas fluidly connected with the bearing and a control system (134) for regulating the supply of pressurized gas to the bearing in dependence on the rotational speed of the moving part. The system has particular application in a turbocharger (1) where a flow of pressurized gas from the source is introduced into the bearing at the start-up and slow down phases of operation of the turbocharger, the flow being stopped, or reduced, when the turbocharger has reached normal operating speeds.