Abstract: A centrifugal compressor includes: a compressor impeller; a motor including a stator and a rotor; and a housing. The rotor includes a tubular member, a magnetic body, a first shaft member and a second shaft member, an axial passage, and a plurality of radial passages. A dimension of each of the radial passages in a circumferential direction of the second shaft member gradually increases toward a radially outward side of the second shaft member. Each of the radial passages includes an opening that is opened at the outer peripheral surface of the second shaft member. The outer peripheral surface of the second shaft member has an interposed surface that is interposed between the opening of one of the radial passages and the opening of another of the radial passages adjacent to each other in the circumferential direction of the second shaft member.

Abstract: A turbo fluid machine includes a housing having a motor chamber, a turbine chamber, a first shaft hole, and a second shaft hole; a drive shaft; and a sealing member that seals a gap between the motor chamber and the turbine chamber. The sealing member includes a first sealing member and a second sealing member that is located away from the first sealing member and between the first sealing member and the turbine chamber in an axial direction of the drive shaft. The drive shaft, the second shaft hole, the first sealing member, and the second sealing member cooperate to form a reservoir in which water contained in exhaust from a fuel cell is stored. The housing has a water discharge passage which is communicated with the reservoir and through which the water is discharged from the reservoir to an outside of the housing.

Abstract: A foil bearing includes a top foil, which includes a bearing surface facing a rotary member, extends in a circumferential direction, and includes a fixed end at one end in the circumferential direction and a free end at the other end in the circumferential direction, and a sheet-shaped back foil, which elasticity supports the top foil. The top foil includes a connecting section that connects, at a location between the fixed end and the free end, a first side of the top foil, at which the bearing surface is located, to a second side of the top foil, at which the back foil is located, and a cutout section that reduces the thickness of the top foil so as to facilitate deformation of the top foil. The cutout section is formed at the second side rather than the first side.

Abstract: A centrifugal compressor includes: a compressor impeller; a motor including a stator and a rotor; and a housing. The rotor includes a tubular member, a magnetic body, a first shaft member and a second shaft member, an axial passage, and a plurality of radial passages. A dimension of each of the radial passages in a circumferential direction of the second shaft member gradually increases toward a radially outward side of the second shaft member. Each of the radial passages includes an opening that is opened at the outer peripheral surface of the second shaft member. The outer peripheral surface of the second shaft member has an interposed surface that is interposed between the opening of one of the radial passages and the opening of another of the radial passages adjacent to each other in the circumferential direction of the second shaft member.

Abstract: A turbo fluid machine includes a housing having a motor chamber, a turbine chamber, a first shaft hole, and a second shaft hole; a drive shaft; and a sealing member that seals a gap between the motor chamber and the turbine chamber. The sealing member includes a first sealing member and a second sealing member that is located away from the first sealing member and between the first sealing member and the turbine chamber in an axial direction of the drive shaft. The drive shaft, the second shaft hole, the first sealing member, and the second sealing member cooperate to form a reservoir in which water contained in exhaust from a fuel cell is stored. The housing has a water discharge passage which is communicated with the reservoir and through which the water is discharged from the reservoir to an outside of the housing.

Abstract: A centrifugal compressor includes a compressor impeller that compresses air, a motor rotating the compressor impeller, and a housing including an impeller chamber, a motor chamber, and an inlet from which the air is drawn into the impeller chamber. The motor includes a stator and a rotor including a tubular member, a magnetic body, and a first shaft member and a second shaft member. The rotor includes an axial passage, a radial passage, and a connecting rod connecting the first shaft member with the second shaft member and forming a gap serving as a part of the axial passage. The housing includes a discharge port from which the air is discharged to an outside of the housing. The air outside the housing is introduced from the inlet into the motor chamber through the axial passage and the radial passage to cool the magnetic body.

Abstract: A fuel cell fluid machine includes a rotary shaft, an electric motor, a compression unit, and a rotation assist unit. The rotation assist unit includes a turbine wheel and a turbine housing. Exhaust gas discharged from a fuel cell stack is introduced to the turbine chamber. The exhaust gas then flows in the radial direction of the rotary shaft and is discharged in the axial direction of the rotary shaft. This rotates the turbine wheel. A diameter of the turbine wheel and a diameter of the shroud surface gradually increase from an upstream side to a downstream side in a flowing direction of the exhaust gas.

Abstract: A centrifugal compressor includes a motor cooling passage through which cooling fluid for cooling an electric motor flows, an air passage through which cooling air for cooling a first air bearing and a second air bearing is supplied to each of the first air bearing and the second air bearing, and a heat exchanger cooling the cooling air. The motor cooling passage includes a plurality of cooling axial passages having a first cooling axial passage through which the cooling fluid is supplied to the heat exchanger and a second cooling axial passage through which the cooling fluid is discharged from the heat exchanger. The heat exchanger has a first port communicating with the first cooling axial passage, a second port communicating with the second cooling axial passage, and a third port communicating with an air axial passage extending in an axial direction of a rotary shaft.

Abstract: A fluid machine includes a bladed wheel, a resolver, a first fastener, and a second fastener. A resolver rotor is held between the first fastener and the rotary shaft and fixed to a large-diameter portion of the rotary shaft. The bladed wheel is held between the second fastener and the rotary shaft and fixed to a small-diameter portion of the rotary shaft. While the resolver rotor is fixed by the first fastener in a same direction as the bladed wheel is fixed by the second fastener along an axial direction of the rotary shaft, and the resolver rotor is fixed by the first fastener at a position away in a radial direction of the rotary shaft from a position where the bladed wheel is fixed by the second fastener so that the resolver rotor does not receive an axial force from the second fastener.

Abstract: A fluid machine includes a housing and a motor. The motor includes a rotor and a stator having a stator core. The rotor includes a tubular portion, a magnetic member, and a plug that is provided at one of a first end a second end of the tubular portion. The tubular portion includes first and second portions that protrude in an axial direction in relation to opposite ends of the stator core and opposite ends of the magnetic member. The first and second portions of the tubular portions are rotatably supported by two bearings, respectively. The magnetic member is spaced apart in the axial direction from the plug so that a space is defined in the tubular portion by the tubular portion, the magnetic member, and the plug. One of the two bearings is provided on a radially outer side of the space.

Abstract: A turbo fluid machine includes a housing, a rotating member, and a motor. Part of fluid compressed by a compressor impeller is introduced into a motor accommodation space through an inlet-side flow passage that has an inlet-side fixed throttle, and is discharged from the motor accommodation space through an outlet-side flow passage that has an outlet-side fixed throttle. The outlet-side flow passage includes a connection part connecting to the motor accommodation space. The connection part is formed separately from a clearance between a second partition wall and a shaft, and is located opposite to a connection part of the inlet-side flow passage connecting to the motor accommodation space across the motor in an axial direction of the shaft. The inlet-side fixed throttle and the outlet-side fixed throttle are configured such that pressure in the motor accommodation space is higher than pressure in a turbine-wheel back pressure region.

Abstract: A fuel cell system includes a target pressure value for the pressure in a fuel cell is set depending on a demand output value to the fuel cell. A turbine retains a set pressure line representing a relationship between an airflow rate supplied to the turbine and a pressure ratio corresponding to a ratio of a pressure upstream of the turbine and a pressure downstream of the turbine. A controller executes a first control when the target pressure value for the fuel cell is lower than the set pressure line and executes a second control when the target pressure value for the fuel cell is higher than the set pressure line. The controller controls an outlet valve so as not to be fully opened when a turbine bypass valve is fully closed.

Abstract: A fuel cell system includes a target pressure value for the pressure in a fuel cell is set depending on a demand output value to the fuel cell, A turbine retains a set pressure line representing a relationship between an airflow rate supplied to the turbine and a pressure ratio corresponding to a ratio of a pressure upstream of the turbine and a pressure downstream of the turbine. A controller executes a first control when the target pressure value for the fuel cell is lower than the set pressure line and executes a second control when the target pressure value for the fuel cell is higher than the set pressure line. The controller controls an outlet valve so as not to be fully opened when a turbine bypass valve is fully closed.

Abstract: A turbo fluid machine includes a housing, a rotating member, and a motor. Part of fluid compressed by a compressor impeller is introduced into a motor accommodation space through an inlet-side flow passage that has an inlet-side fixed throttle, and is discharged from the motor accommodation space through an outlet-side flow passage that has an outlet-side fixed throttle. The outlet-side flow passage includes a connection part connecting to the motor accommodation space. The connection part is formed separately from a clearance between a second partition wall and a shaft, and is located opposite to a connection part of the inlet-side flow passage connecting to the motor accommodation space across the motor in an axial direction of the shaft. The inlet-side fixed throttle and the outlet-side fixed throttle are configured such that pressure in the motor accommodation space is higher than pressure in a turbine-wheel back pressure region.

Abstract: A turbomachine includes a housing, an impeller, a shaft, and first and second radial foil bearings that rotationally support the shaft. The motor includes a stator and a rotor. The shaft includes a first inner ring and a second inner ring. The first inner ring is formed integrally with the shaft as a part of the shaft. The second inner ring is formed separately from the shaft. The first inner ring includes a first opposed end portion that is opposed to a first end portion of the rotor. The second inner ring includes a second opposed end portion that is opposed to a second end portion of the rotor. The second opposed end portion is fixed to the shaft such that the second opposed end portion and the first opposed end portion hold the rotor in between to apply preload in an axial direction to the rotor.

Abstract: A hydrogen circulation pump includes a pump body, a motor, a driver, and a housing. The housing internally includes a hydrogen recirculation passage connecting the pump body to a fuel cell stack, a hydrogen supply passage through which hydrogen is supplied from a hydrogen supply source to the fuel cell stack, and a partition wall that defines an accommodation chamber accommodating the driver. The hydrogen supply passage includes a merge portion where the hydrogen supply passage merges with the hydrogen recirculation passage. The hydrogen supply passage is arranged in the housing such that heat is exchanged at an upstream side of the merge portion through the partition wall between the driver and the hydrogen in the hydrogen supply passage.

Abstract: A centrifugal compressor includes a housing, a rotary shaft accommodated in the housing, an electric motor including a motor rotor and a motor stator for rotating the rotary shaft, an impeller connected to one end of the rotary shaft and driven by rotation of the rotary shaft so as to compress fluid, a radial bearing rotatably supporting the rotary shaft in a radial direction of the rotary shaft, and a resolver including a resolver rotor and a resolver stator for detecting a rotation angle of the motor rotor. The resolver rotor is fixed to the other end of the rotary shaft opposite to the impeller. The rotary shaft includes a radial support member rotatably supported by the radial bearing, and a radius of the radial support member is larger than a radius of gyration of the resolver rotor.

Abstract: A fuel cell system includes a bypass passage, a flow path selector portion that selects a flow path of oxidation gas, and a valve opening adjusting portion that adjusts an opening of a pressure adjusting valve. Until a rotation speed of a rotary shaft reaches a separation rotation speed at which the rotary shaft is separated from an aerodynamic bearing, the flow path selector portion permits flow of the oxidation gas from an electric compressor to a fuel cell stack through a supply passage and flow of the oxidation gas from the electric compressor to a discharge passage through the supply passage and the bypass passage, and the valve opening adjusting portion adjusts the opening of a pressure adjusting valve so that an efficiency of a turbine is maximized by the discharge gas.

Abstract: A waste heat utilization apparatus of a first embodiment includes a driving system including an engine and a turbocharger supplying pressurized air to the engine, and a Rankine cycle system used for the driving system. The Rankine cycle system includes a coolant boiler causing heat exchange between coolant as heating medium and working fluid, and a pressurized air boiler causing heat exchange between the pressurized air as heating medium and the working fluid. A first bypass channel for allowing the working fluid to bypass the coolant boiler and a three-way valve are provided in the Rankine cycle system. In the waste heat utilization apparatus, the amount of heat absorbed in the working fluid in the coolant boiler can be reduced by flowing the working fluid into the first bypass channel.

Abstract: In a waste-heat recovery system, a gear pump and an electric motor share a drive shaft. A pump interior portion and a motor interior portion are partitioned from each other by a shaft seal, and the pump interior portion defines a part of a circulation path of a Rankine cycle circuit. One end of a communication path that is communicated to the motor interior portion is connected to a bottom portion of a housing, and the other end of the communication path is connected to the circulation path at a position between an expander and a condenser in the Rankine cycle circuit.