Abstract: A thrust foil bearing includes: a base plate including an insertion hole through which a shaft is inserted, and a supporting surface expanding in a direction orthogonal to an axial direction of the insertion hole; a step member placed on the supporting surface and formed of a different body from the base plate; and a back foil extending in a circumferential direction of the insertion hole and in which one part of the back foil is supported by the supporting surface and another part of the back foil next to the one part in the circumferential direction is supported by the step member.

Abstract: A surface magnet rotor includes a shaft member extending along a rotational axis, and a magnet portion formed around the shaft member and forming opposite magnetic poles arranged along a circumferential direction. A cross-section of the shaft member includes an intermediate line extending from the rotational axis to a center point in the circumferential direction between a d-axis and a q-axis of the magnet portion. In the cross-section, a first cross-sectional area delimited by the d-axis and the intermediate line is different from a second cross-sectional area delimited by the q-axis and the intermediate line.

Abstract: A rotary machine includes a rotary shaft with an axial disc; an axial magnetic bearing which supports the rotary shaft; a motor which rotates the rotary shaft; a turbine impeller mounted on one end portion of the rotary shaft; a compressor impeller mounted on the other end portion; a cooling gas flow passage where a cooling gas for cooling the motor flows; and a housing for at least the motor, the axial magnetic bearing, and the axial disc. The motor includes a rotor unit on the rotary shaft, and a stator unit facing the rotor unit, the axial disc is equipped with a pair of load receiving surfaces sandwiched between the axial magnetic bearings, and the cooling gas flow passage is equipped with a first flow passage between the rotor unit and the stator unit, and a second flow passage extending along at least one of the load receiving surface.

Abstract: A turbo refrigerator is provided with: a turbo compressor having a motor; an oil cooling unit which cools lubricating oil which is supplied to at least a portion of the turbo compressor; a refrigerant introduction part which introduces some of the refrigerant which circulates between an evaporator and a condenser into a motor accommodation space and the oil cooling unit; and a cooling unit which cools the refrigerant which is introduced into the motor accommodation space and the oil cooling unit.

Abstract: A liquid level indicator including a liquid level calm portion that is provided with a liquid introduction inlet that communicates with a portion below the liquid level in an oil tank and a gas vent that communicates with a portion above the liquid level; and a sight glass for observing a liquid level in the liquid level calm portion, having a liquid introduction tube provided with an extension portion that communicates with the liquid introduction inlet and extends toward the bottom portion of the oil tank, and a distal end portion that communicates with the extension portion and opens in a direction other than the downward direction below the liquid level.

Abstract: A turbo compressor that has a pressure equalizing tube that circulates a gas from a gear unit accommodation space toward an IGV accommodation space, and an oil separation device that is provided in the gear unit accommodation space to separate lubricating oil that is contained in the gas, in which the oil separating device has a suction duct that communicates with the pressure equalizing tube, and the suction duct has a centrifugal separation portion provided with a first demister, a second demister provided on the downstream side of the first demister in relation to the suction direction, and a curved passage provided between the first demister and the second demister.

Abstract: A turbo-compressor including a variable vane that adjusts the flow rate of a fluid, a drive shaft that is connected to the variable vane and is rotated to drive the variable vane, a motor that rotationally drives the drive shaft, and a coupling that couples the drive shaft with an output shaft of the motor. Between the drive shaft and output shaft and the coupling, a vibration isolation means is arranged to connect the drive shaft and output shaft to each other so that they rotate together and allow the drive shaft and output shaft to move in a vibration direction.

Abstract: A turbo compressor that has a compression stage provided with an impeller that rotates; a housing provided with a gear unit accommodation space that accommodates lubricating oil and accommodates a large diameter gear that transmits rotating force to the impeller, an IGV accommodation space in which the ambient pressure is lower than the gear unit accommodation space, and a gap that brings the IGV accommodation space and the air intake side of a first compression stage into communication; a pressure equalizing tube that causes a gas to circulate from the gear unit accommodation space toward the IGV accommodation space; and a second oil separating device that separates, in the IGV accommodation space, the lubricating oil contained in the gas.

Abstract: A turbo refrigerator is provided with: a turbo compressor having a motor; an oil cooling unit which cools lubricating oil which is supplied to at least a portion of the turbo compressor; a refrigerant introduction part which introduces some of the refrigerant which circulates between an evaporator and a condenser into a motor accommodation space and the oil cooling unit; and a cooling unit which cools the refrigerant which is introduced into the motor accommodation space and the oil cooling unit.

Abstract: A turbo compressor that has a pressure equalizing tube that circulates a gas from a gear unit accommodation space toward an IGV accommodation space, and an oil separation device that is provided in the gear unit accommodation space to separate lubricating oil that is contained in the gas, in which the oil separating device has a suction duct that communicates with the pressure equalizing tube, and the suction duct has a centrifugal separation portion provided with a first demister, a second demister provided on the downstream side of the first demister in relation to the suction direction, and a curved passage provided between the first demister and the second demister.

Abstract: A turbo compressor that has a compression stage provided with an impeller that rotates; a housing provided with a gear unit accommodation space that accommodates lubricating oil and accommodates a large diameter gear that transmits rotating force to the impeller, an IGV accommodation space in which the ambient pressure is lower than the gear unit accommodation space, and a gap that brings the IGV accommodation space and the air intake side of a first compression stage into communication; a pressure equalizing tube that causes a gas to circulate from the gear unit accommodation space toward the IGV accommodation space; and a second oil separating device that separates, in the IGV accommodation space, the lubricating oil contained in the gas.

Abstract: A liquid level indicator including a liquid level calm portion that is provided with a liquid introduction inlet that communicates with a portion below the liquid level in an oil tank and a gas vent that communicates with a portion above the liquid level; and a sight glass for observing a liquid level in the liquid level calm portion, having a liquid introduction tube provided with an extension portion that communicates with the liquid introduction inlet and extends toward the bottom portion of the oil tank, and a distal end portion that communicates with the extension portion and opens in a direction other than the downward direction below the liquid level.

Abstract: An electrical motor includes a motor case, a rotor that is housed in the motor case and rotatable about a rotor shaft, a stator that is provided around the rotor in the motor case and configured by winding a stator coil around a stator core, and a first spray nozzle that is provided in the motor case for spraying liquid coolant toward an inner circumferential surface of the motor case. The stator coil has a first coil end protruded from the stator core along a direction of the rotor shaft. The first spray nozzle is configured to spread the coolant as mist by splashing the coolant on the inner circumferential surface to make the spread mist over the first coil end. The first coil end can be cooled sufficiently by vaporization heats of the mist coolant that is fallen over it.

Abstract: A turbo-compressor 1 includes a variable vane 3 that adjusts the flow rate of a fluid, a drive shaft 5 that is connected to the variable vane 3 and is rotated to drive the variable vane 3, a motor 7 that rotationally drives the drive shaft 5, and a coupling 11 that couples the drive shaft 5 with an output shaft 9 of the motor 7. Between the drive shaft 5 and output shaft 9 and the coupling 11, a vibration isolation means 13 is arranged to connect the drive shaft 5 and output shaft 9 to each other so that they rotate together and allow the drive shaft 5 and output shaft 9 to move in a vibration direction.

Abstract: A heat insulating structure for an expansion turbine includes an adiabatic expansion device including an expander body that includes an outlet passage for refrigerant fluid at a central portion thereof and an introduction chamber for refrigerant fluid communicating with an inlet of the outlet passage on an outer peripheral portion thereof, and a turbine impeller that is rotatably provided at the inlet and braked by a braking device. The adiabatic expansion device adiabatically expands refrigerant fluid by rotating the turbine impeller with refrigerant fluid that flows from the introduction chamber to the outlet passage side. A heat-insulating layer, which surrounds the entire periphery of the outlet passage over the entire length of the introduction chamber, is formed between the introduction chamber and the outlet passage. Accordingly, it is possible to improve turbine efficiency by reducing transfer of heat of refrigerant fluid from the introduction chamber to the outlet passage.

Abstract: A braking mechanism is provided that is suitable for an expansion turbine that rotates at high speed. Upper end salient poles 26a and 26b are formed in two opposite places on the outer peripheral upper end of a rotating shaft 12, and lower end salient poles 28a and 28b are formed in two opposite places on the outer peripheral lower end of the rotating shaft 12 such that they are staggered in the vertical direction with respect to the upper end salient poles 26a and 26b. A casing 22 is provided in a location facing an outer periphery of the rotating shaft 12, and an excitation coil 30 is provided on the casing 22 for forming a magnetic path between the upper end salient poles 26a and 26b and the lower end salient poles 28a and 28b. By rotation of the rotating shaft 12, and by the magnetic path formed by the excitation coil 30, eddy currents are generated in the casing 22.

Abstract: Expansion turbine having a variable nozzle mechanism comprises an adiabatic expansion device located in a vacuum container having a turbine impeller therein which rotates and drives the turbine impeller during adiabatic expansion of very low temperature gas, and varies the throat area of very low temperature gas introduced in the turbine impeller by driving a nozzle member disposed near the outside end of the adiabatic expansion device by a drive force from a driving member located outside the vacuum container; wherein the driving member comprises a cylindrical member disposed coaxially with the turbine impeller, and the nozzle member is provided on the extension of the body of the cylindrical member in the axial direction.

Abstract: Expansion turbine having a variable nozzle mechanism comprises an adiabatic expansion device located in a vacuum container having a turbine impeller therein which rotates and drives the turbine impeller during adiabatic expansion of very low temperature gas, and varies the throat area of very low temperature gas introduced in the turbine impeller by driving a nozzle member disposed near the outside end of the adiabatic expansion device by a drive force from a driving member located outside the vacuum container; a plate member provided detachably in contact with the outside end of the body of the adiabatic expansion device, wherein the support side of the nozzle member is connected to and supported by the plate member, and the drive side of the nozzle member is connected to and supported by the driving member.

Abstract: A cryogenic refrigerator (10) which generates a cryogenic temperature by compressing and expanding a working gas in a closed loop (11). The cryogenic refrigerator comprises a bypass line (22) allowing a high-pressure portion and a low-pressure portion to communicate with each other, a gas storage tank (24) located midway in the bypass line and having pressure regulation valves (23a, 23b) on the high-pressure side and the low-pressure side, respectively, and a pressure control unit (26) controlling the pressure regulation valves. The pressure control unit (26) controls the pressure regulation valves (23a, 23b) so that the pressure in the gas storage tank (24) is equal to the pressure in the closed loop at room temperature and in a stopped state and so that the pressure in the gas storage tank (24) is between the pressures in the high-pressure portion and in the low-pressure portion and is close to the pressure in the low-pressure portion in an operating state.

Abstract: A braking mechanism is provided that is suitable for an expansion turbine that rotates at high speed. Upper end salient poles 26a and 26b are formed in two opposite places on the outer peripheral upper end of a rotating shaft 12, and lower end salient poles 28a and 28b are formed in two opposite places on the outer peripheral lower end of the rotating shaft 12 such that they are staggered in the vertical direction with respect to the upper end salient poles 26a and 26b. A casing 22 is provided in a location facing an outer periphery of the rotating shaft 12, and an excitation coil 30 is provided on the casing 22 for forming a magnetic path between the upper end salient poles 26a and 26b and the lower end salient poles 28a and 28b. By rotation of the rotating shaft 12, and by the magnetic path formed by the excitation coil 30, eddy currents are generated in the casing 22.