A ventilation fan includes a shaft assembly, a rotor, a motor housing, and a bearing housing. The shaft assembly defines a first port and a second port. The rotor has a rotor first portion disposed about a first portion of the shaft assembly and a rotor second portion that extends from the rotor first portion. The rotor first portion defines a rotor port. The motor housing is disposed about a second portion of the shaft assembly. The motor housing defines a housing port. The bearing housing is operatively connected to the motor housing. The bearing housing is disposed about a third portion of the shaft assembly.

A hybrid bearing system for gas turbine engines is disclosed. The hybrid bearing system comprises ball/roller bearings and air bearings. For horizontal applications, compressed air injected into the air bearing provides a lift force such that enables the rotating shaft for the turbine to float freely. The compressed air is also employed to cool the ball/roller bearings. Hence, given the reduced friction on the ball/roller bearings due to the free-floating shaft, as well as the air cooling of the ball/roller bearings, typical lubrication systems are not necessary. For vertical applications, the compressed air provides cooling to the ball/roller bearings which renders the need for conventional lubrication systems unnecessary.

Aspects of the disclosure are directed to a system associated with an engine of an aircraft, the system comprising: a fluid source that is configured to provide a fluid at a first pressure value, a carbon seal, a seal plate that includes at least one lift-off feature that interfaces to the carbon seal, and a pressure boosting mechanism configured to obtain the fluid from the fluid source, increase the pressure of the fluid to a second pressure value, and provide the fluid at the second pressure value to the at least one lift-off feature.

A gas floated workpiece supporting apparatus includes a gas upward ejector ejecting gas upward, and a gas downward ejector located at an upper side from the gas upward ejector and ejecting gas downward. The gas downward ejector is installed at a position where the gas downward ejector ejects the gas downward from above a plate-shaped workpiece to apply pressure to the plate-shaped workpiece that is floated and supported by the gas ejected from the gas upward ejector, whereby a uniform floating amount supports the plate-shaped workpiece with high flatness at a time of floating and supporting the plate-shaped workpiece.

Embodiments of a gas bearing for aircraft engines are provided herein. In some embodiments, a gas bearing may include a first shaft; a second shaft disposed concentrically about the first shaft; and a protrusion extending from at least one of an inner surface of the first shaft or the outer surface of the second shaft to form a gap between the first shaft and the second shaft.

In a material testing machine including a load actuator including a shaft configured to make a linear motion, and configured to apply a load to a test piece through the linear motion of the shaft, the load actuator includes a bearing configured to support the shaft, and the bearing serves as an air bearing.

A two stage centrifugal compressor including a first impeller and a second impeller rigidly coupled via a rotational shaft, an electric motor for driving the rotational shaft, the first impeller configured to compress a low pressure fluid to generate a pressurized fluid, a first fluid flow channel to couple a first portion of the pressurized fluid to a first static gas thrust bearing for supporting the first impeller, a second fluid flow channel to couple a second portion of the pressurized fluid to the second impeller, the second impeller configured to compress the pressurized fluid to generate a high pressure fluid, a third fluid flow channel to couple a first portion of the high pressure fluid to a second static gas thrust bearing for supporting the second impeller, and a second fluid flow channel to couple a second portion of the pressurized fluid to an output.