A rotary machine includes a compression section that is disposed between the pair of radial bearings in a casing and compresses a fluid, an expansion section that is disposed side by side with the compression section and expands the fluid, and a thrust bearing that is disposed at a position close to a first end portion or a second end portion of a rotary shaft in an axial direction with respect to the compression section and the expansion section. Among a compression section suction port, a compression section discharge port, an expansion section suction port, and an expansion section discharge port, the compression section suction port is disposed at a position closest to the first end portion in the axial direction, and the expansion section discharge port is disposed at a position closest to the second end portion in the axial direction.

A compressor system includes a compressor housing and a driveshaft rotatably supported within the compressor housing. The compressor system further includes an impeller that imparts kinetic energy to incoming refrigerant gas upon rotation of the driveshaft, a thrust disk coupled to the driveshaft, and a bearing assembly mounted to the compressor housing. The impeller includes an impeller bore having an inner surface, and the thrust disk includes an outer disk and a hub. The bearing assembly rotatably supports the outer disk of the thrust disk. The hub is disposed within the impeller bore, and includes a hub outer surface in contact with the inner surface of the impeller bore. A first contact force between the hub outer surface and the inner surface of the impeller bore increases with increased rotational speed of the driveshaft.

An electric blower includes a motor, a first rotor blade provided on one end side of the motor in an axial direction, a second rotor blade provided on another side of the motor opposite to the first rotor blade in the axial direction, and a first stator blade provided to face the first rotor blade.

An electric motor system includes a drive shaft, first and second magnetic bearing portions facing each other and supporting the drive shaft, an electric motor to rotate the drive shaft, and a gap detection unit to detect a position of the drive shaft During rotation of the drive shaft, greater external force acts, on average, on the drive shaft in a first direction than in a second direction. The first and second direction extend from the second and first magnetic bearing portions to the first and second magnetic bearing portion. The first and second magnetic bearing portions produce first and second magnetic forces on the drive shaft in the first and second directions. A magnitude of the second magnetic force is greater than a magnitude of the first magnetic force. The gap detection unit is arranged closer to the second magnetic bearing portion than to the first magnetic bearing portion.

An air blower capable of suppressing movement of an impeller in a thrust direction is provided. A first case includes a first air inlet and a first air outlet. A second case includes a second air inlet communicating with the first air inlet and a second air outlet communicating with the first air outlet. An impeller is provided inside the second case. A motor rotates the impeller. A first flow channel is provided between the motor and the second case on the opposite side of the first air inlet and the second air inlet relatively to the impeller. A second flow channel is provided between the first case and the second case and communicates with the first flow channel, the first air inlet, and the second air inlet.

An electric motor system includes a drive shaft, first and second magnetic bearing portions facing each other and supporting the drive shaft, an electric motor to rotate the drive shaft, and a gap detection unit to detect a position of the drive shaft During rotation of the drive shaft, greater external force acts, on average, on the drive shaft in a first direction than in a second direction. The first and second direction extend from the second and first magnetic bearing portions to the first and second magnetic bearing portion. The first and second magnetic bearing portions produce first and second magnetic forces on the drive shaft in the first and second directions. A magnitude of the second magnetic force is greater than a magnitude of the first magnetic force. The gap detection unit is arranged closer to the second magnetic bearing portion than to the first magnetic bearing portion.

A heating, ventilation, air conditioning, and refrigeration (HVACR) system includes a compressor with a gas bearing supplied with compressed gas and a controller. The controller is configured to determine an inlet pressure and outlet pressure of the gas bearing, determine a maximum speed limit based on the inlet pressure and the outlet pressure, and prevent the compressor from operating at a speed that is greater than the maximum speed limit. A method of controlling a compressor includes calculating a maximum speed limit based on an inlet pressure and an outlet pressure of the gas bearing. The method also includes in response to determining that a speed setting is greater than the maximum speed limit, adjusting operation of the compressor such that a speed of the compressor is at or below the maximum speed limit.

A heat transfer circuit includes a compressor, a condenser, an expander, and an evaporator that are fluidly connected together. The compressor includes a housing and a shaft rotatable relative to the housing to compress a working fluid received at a suction inlet, in which the shaft is supported by a gas bearing, and the gas bearing including a bearing housing having a fluid inlet and an outlet. A high pressure gas source is fluidly connected to the fluid inlet of the bearing housing for supplying high pressure fluid to the fluid inlet of the gas bearing such that the gas bearing supports the shaft when the shaft is rotating. A pressure reducer is connected to the outlet of the gas bearing is provided for reducing a vent pressure of the gas bearing.

A centrifugal compressor, including: a housing; a motor assembly disposed in the housing and a motor cavity and a motor shaft located in the motor cavity, the motor shaft having a first end and a second end extending from the motor cavity; a first impeller assembly located at the first end of the motor shaft and provided with a first labyrinth sealing mechanism; a second impeller assembly located at the second end of the motor shaft and provided with a second labyrinth sealing mechanism; a first gas bearing assembly provided between the motor cavity and the first impeller assembly; and a second gas bearing assembly provided between the motor cavity and the second impeller assembly; wherein the first labyrinth sealing mechanism is kept in gas communication with the first gas bearing assembly, and the second labyrinth sealing mechanism is kept in gas communication with the second gas bearing assembly.

A centrifugal compressor, including: a housing; a motor assembly disposed in the housing and a motor cavity and a motor shaft located in the motor cavity, the motor shaft having a first end and a second end extending from the motor cavity; a first impeller assembly located at the first end of the motor shaft and provided with a first labyrinth sealing mechanism; a second impeller assembly located at the second end of the motor shaft and provided with a second labyrinth sealing mechanism; a first gas bearing assembly provided between the motor cavity and the first impeller assembly; and a second gas bearing assembly provided between the motor cavity and the second impeller assembly; wherein the first labyrinth sealing mechanism is kept in gas communication with the first gas bearing assembly, and the second labyrinth sealing mechanism is kept in gas communication with the second gas bearing assembly.