Abstract: A fuel cell system includes a fuel cell stack, a hydrogen supply source, a hydrogen flow passage, a hydrogen recirculation passage, and a hydrogen circulation pump configured to recirculate emission gas containing hydrogen from the fuel cell stack through the hydrogen recirculation passage. The hydrogen circulation pump includes a pump body, a motor, and a housing. The housing internally includes a merge portion that merges the hydrogen recirculation passage with the hydrogen flow passage. The hydrogen flow passage includes a bypass passage that bypasses the merge portion by branching from a portion of the hydrogen flow passage between the hydrogen supply source and the merge portion. The hydrogen flow passage or the bypass passage includes an open degree control valve configured to control a flow rate of hydrogen flowing through the hydrogen flow passage and the bypass passage.

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 hydrogen circulation pump for a fuel cell includes a housing, rotary shafts, and two-lobe rotors. Each of the rotors has a configuration defined by the profile defined by an arc having a radius R and extending from apex end to a first transition point, an involute curve extending from the first transition point to a second transition point, and an envelope curve formed continuously with the involute curve from the second transition point to the bottom end based on a basic circle having a radius r?. A distance between the apex ends of the lobe portions of each of the rotors is D. A distance between the axes of the pair of the rotary shafts is L. The radius R is set in {(?2)/16}?L<R<{(27?5?2)/56}L, and the radius r is set in L/(2?2)<r<0.3(?2)L, and the radius r? is set in ?/(4?2)L<r?<1.28?/(4?2)L, and the distance D is set in 2{L+?/(4?2)L}<D<2.032{L+?/(4?2)L}.

Abstract: A pump mounting structure is disclosed. The structure includes a mounting surface on a body having an insertion recess, and at least one mounting member having a mounting portion inserted into the insertion recess. The mounting portion has an outer surface and an insertion hole through which a bolt is inserted. A first gap is formed between the insertion hole and the bolt. A second gap is formed between the outer surface of the mounting portion and an inner surface of the insertion recess. A seal member is disposed on an open side of the insertion recess.

Abstract: A compressor, which is cooled by cooling medium, includes a compression chamber, a first cooling chamber and a second cooling chamber. In the compression chamber, gas is compressed and then discharged therefrom. The first cooling chamber, in which the cooling medium flows, is provided so as to adjoin the compression chamber for cooling the gas in the compression chamber. The second cooling chamber adjoins the first cooling chamber. The second cooling chamber has a gas passage in which the discharged gas flows and a medium passage in which the cooling medium flows. The medium passage is arranged so as to restrain transmission of heat of the discharged gas in the gas passage to the cooling medium in the first cooling chamber.

Abstract: A compressor has a compression unit for compressing gas to a desired pressure, a drive shaft and a balancer. The drive shaft is connected to the compression unit for driving the compression unit. Imbalance on the drive shaft is generated due to movement of the compression unit. The balancer is mounted on the drive shaft and includes a main portion and adjustable portion for correcting the imbalance on the drive shaft. Preferably, at least one of the weight and the shape of the adjustable portion is adjustable.

Abstract: A motor-driven Roots compressor includes a drive shaft driven by a motor and a driven shaft connected to a drive shaft through a timing gear. A pair of rotors is respectively fixed to the drive shaft and the driven shaft. The rotors are rotated so that the compressor draws and discharges working fluid. The compressor also includes a casing having a plurality of shells which define a motor chamber for accommodating the motor, a gear chamber for accommodating the timing gear and a rotor chamber for accommodating the pair of rotors. A refrigerant passage is formed in at least one of the shells of the motor chamber and the gear chamber for flowing the working fluid therein. At least one of the motor and the timing gear is cooled by the working fluid in the refrigerant passage.

Abstract: A starting system for a pump includes a driving motor, an electric source, a selector switch, a starter sensor, a temperature sensor and a control unit. The selector switch is located between the driving motor and the electric source for reversing polarity of the electric power supplied from the electric source to the driving motor. The starter sensor senses whether or not the driving motor has been started. The temperature sensor senses a temperature. The control unit operates the selector switch so as to repeatedly give the driving motor indications of reverse rotation and normal rotation in a case where the starter sensor does not sense that the driving motor has been started even if the control unit operates the selector switch so as to give the driving motor the indication of normal rotation in a state where the temperature sensed by the temperature sensor is below a preset temperature.

Abstract: A compressor includes a housing member having a through hole. The compressor includes a conductive portion through which external electricity is supplied to a motor mechanism. The conductive portion has a lead extending from the motor mechanism, and a connector terminal. The connector terminal is connected to the lead to permit the external electricity to be conducted to the lead. The connector terminal is attached to the through hole such that a joint between the lead and the connector terminal is located in the through hole to face inward of the housing member. A viscoelastic insulating material fills the through hole. Therefore, the compressor ensures reliable insulation of the terminal from a housing member.

Abstract: A fluid machine includes a motor and a motor housing. The motor housing defines a motor chamber for accommodating the motor. The motor chamber is filled with inert gas. A rotor rotates in accordance with rotation of the motor. A pump housing defines a pump chamber for accommodating the rotor. A dividing wall is located between the pump housing and the motor housing. The pump housing and the motor housing are attached to each other via the dividing wall. Therefore, water is prevented from being generated in the motor chamber even if fluid that contains hydrogen leaks from the pump chamber to the motor chamber.

Abstract: A fuel cell system includes a fuel cell stack, a hydrogen flowing passage, an air flowing passage and a control valve. At least one of the gas flowing passages includes a bypass, a selecting means, a gas flowing means and a control unit. The bypass allows a gas to flow therethrough so as to detour the fuel cell stack and the control valve. The selecting means selects one of a passage which passes through the fuel cell stack and the bypass. The gas flowing means flows the gas to the bypass. In the control unit, the through passage is selected by the selecting means when the system is operated, The bypass is selected by the selecting means when the operation of the system is stopped. The gas is flowed to the bypass by operating the gas flowing means when the control valve is frozen thereby heating the control valve.

Abstract: A starting system for a pump includes a driving motor, an electric source, a selector switch, a starter sensor, a temperature sensor and a control unit. The selector switch is located between the driving motor and the electric source for reversing polarity of the electric power supplied from the electric source to the driving motor. The starter sensor senses whether or not the driving motor has been started. The temperature sensor senses a temperature. The control unit operates the selector switch so as to repeatedly give the driving motor indications of reverse rotation and normal rotation in a case where the starter sensor does not sense that the driving motor has been started even if the control unit operates the selector switch so as to give the driving motor the indication of normal rotation in a state where the temperature sensed by the temperature sensor is below a preset temperature.

Abstract: A compressor has a compression unit for compressing gas to a desired pressure, a drive shaft and a balancer. The drive shaft is connected to the compression unit for driving the compression unit. Imbalance on the drive shaft is generated due to movement of the compression unit. The balancer is mounted on the drive shaft and includes a main portion and adjustable portion for correcting the imbalance on the drive shaft. Preferably, at least one of the weight and the shape of the adjustable portion is adjustable.

Abstract: A compressor has a compression unit for compressing gas to a desired pressure, a drive shaft and a balancer. The drive shaft is connected to the compression unit for driving the compression unit. Imbalance on the drive shaft is generated due to movement of the compression unit. The balancer is mounted on the drive shaft and includes a main portion and adjustable portion for correcting the imbalance on the drive shaft. Preferably, at least one of the weight and the shape of the adjustable portion is adjustable.

Abstract: A compressor, which is cooled by cooling medium, includes a compression chamber, a first cooling chamber and a second cooling chamber. In the compression chamber, gas is compressed and then discharged therefrom. The first cooling chamber, in which the cooling medium flows, is provided so as to adjoin the compression chamber for cooling the gas in the compression chamber. The second cooling chamber adjoins the first cooling chamber. The second cooling chamber has a gas passage in which the discharged gas flows and a medium passage in which the cooling medium flows. The medium passage is arranged so as to restrain transmission of heat of the discharged gas in the gas passage to the cooling medium in the first cooling chamber.

Abstract: A scroll type compressor includes a fixed scroll member and a movable scroll member to define compression chambers. The movable scroll member orbits relative to the fixed scroll member to compress gas in the compression chambers. The compressed gas is discharged to a discharge port. The compressor also includes a filter chamber and a cooling chamber. The filter chamber communicates with the discharge port for accommodating a first filter to at least partially filter the compressed gas. The cooling chamber is located adjacent to the filter chamber for containing coolant fluid that cools the compressed gas in the filter chamber.

Abstract: A scroll type compressor has a housing, a fixed metal scroll member and a movable metal scroll member. The fixed and the movable scroll members each have a base plate and scroll wall extending therefrom. The fixed scroll member is fixed to the housing. The movable scroll member engages the fixed scroll member to trace an orbital motion when driven by a crank mechanism. The scroll members define compression chambers. Resin tip seals are respectively provided on distal ends of the scroll walls and slidably engage the metallic surfaces of the facing base plates. The tip seals seal the compression chambers. A resin coating layer is formed on a region of at least one of the end surfaces of the base plates that is not contacted by a tip seal.

Abstract: A scroll type compressor has a housing, a fixed metal scroll member and a movable metal scroll member. The fixed and the movable scroll members each have a base plate and scroll wall extending therefrom. The fixed scroll member is fixed to the housing. The movable scroll member engages the fixed scroll member to trace an orbital motion when driven by a crank mechanism. The scroll members define compression chambers. Resin tip seals are respectively provided on distal ends of the scroll walls and slidably engage the metallic surfaces of the facing base plates. The tip seals seal the compression chambers. A resin coating layer is formed on a region of at least one of the end surfaces of the base plates that is not contacted by a tip seal.

Abstract: A compressor has a compression unit for compressing gas to a desired pressure, a drive shaft and a balancer. The drive shaft is connected to the compression unit for driving the compression unit. Imbalance on the drive shaft is generated due to movement of the compression unit. The balancer is mounted on the drive shaft and includes a main portion and adjustable portion for correcting the imbalance on the drive shaft. Preferably, at least one of the weight and the shape of the adjustable portion is adjustable.

Abstract: The scroll-type compressor with an integrated motor of the present invention comprises a housing 1, a fixed scroll 21 fixed to the housing 1, a movable scroll 31 installed eccentrically to the fixed scroll 21, and a motor portion 5, and is characterized in that the housing 1 comprises a high pressure chamber 25 to which compressed gases are supplied, a first cooling chamber 26′ installed contiguous to the high pressure chamber 25 and to which cooling fluid is supplied, a second cooling chamber 42 which cools the motor portion 5 and is supplied with the cooling fluid, and a fluid passage 7 that connects the first cooling chamber 26′ and the second cooling chamber 42 and passes the cooling fluid in the direction from the first cooling chamber 26′ to the second cooling chamber 42.