Abstract: In the operation of a refueling screw compressor, when load conditions constantly fluctuate or when the rotation speed control of a cooling fan is performed, it is difficult to accurately perform a diagnosis predicted from measurement results of devices inside the compressor, so a diagnostic mode stably creates an operating condition under which an accurate diagnosis can be performed. In the refueling screw compressor, a discharge electric valve is provided downstream of an air cooler, and an air release electric valve and a dedicated orifice are provided to connect an oil separator inner space and a suction throttle valve space. In the diagnostic mode, the discharge electric valve is closed, the air release electric valve is opened, and while an upstream pressure of the oil separator is maintained at a specified pressure, a rotation speed control operation of a compressor body and the diagnosis of internal devices are performed.

Abstract: A packaged compressor with enhanced electric motor coolability includes an electric motor having an axial direction that lies in a horizontal direction; a compressor body; a housing that houses the electric motor and the compressor body; a cooling air inlet formed through a side surface of the housing; a cooling air outlet formed through an upper surface of the housing; and a cooling fan arranged on a side of the electric motor such that an axial direction of the cooling fan lies in a horizontal direction and crosses the axial direction of the electric motor. The cooling fan has a diameter greater than the height dimension of the electric motor and it's its axial-direction projection plane includes a portion overlapping the electric motor, a portion positioned above the electric motor and not overlapping the electric motor, and a portion positioned below the electric motor and not overlapping the electric motor.

Abstract: In the operation of a refueling screw compressor, when load conditions constantly fluctuate or when the rotation speed control of a cooling fan is performed, it is difficult to accurately perform a diagnosis predicted from measurement results of devices inside the compressor, so a diagnostic mode stably creates an operating condition under which an accurate diagnosis can be performed. In the refueling screw compressor, a discharge electric valve is provided downstream of an air cooler, and an air release electric valve and a dedicated orifice are provided to connect an oil separator inner space and a suction throttle valve space. In the diagnostic mode, the discharge electric valve is closed, the air release electric valve is opened, and while an upstream pressure of the oil separator is maintained at a specified pressure, a rotation speed control operation of a compressor body and the diagnosis of internal devices are performed.

Abstract: A fluid machine that performs efficient cooling of a control system, such as a control device. The fluid machine is provided with: a fluid machine body; a drive source; a control device; a housing in which the fluid machine body, the drive source, and the control device are housed; and a cooling fan. The housing has a plurality of intake openings for introducing cooling air into the interior thereof and one exhaust opening, and includes a partition wall which partitions the interior of the housing into a first compartment and a second compartment and which has a communication portion providing communication between the first compartment and a part of the second compartment. A first intake opening among the plurality of intake openings is disposed in a housing wall of the first compartment in which at least the control device is disposed, and a second intake opening is disposed in a housing wall of the second compartment in which at least the drive source is disposed.

Abstract: A fluid machine that performs efficient cooling of a control system, such as a control device. The fluid machine is provided with: a fluid machine body; a drive source; a control device; a housing in which the fluid machine body, the drive source, and the control device are housed; and a cooling fan. The housing has a plurality of intake openings for introducing cooling air into the interior thereof and one exhaust opening, and includes a partition wall which partitions the interior of the housing into a first compartment and a second compartment and which has a communication portion providing communication between the first compartment and a part of the second compartment. A first intake opening among the plurality of intake openings is disposed in a housing wall of the first compartment in which at least the control device is disposed, and a second intake opening is disposed in a housing wall of the second compartment in which at least the drive source is disposed.

Abstract: The invention is directed to reducing pressure-reduction time while preventing foaming in an oil-separation device during capacity control of a compressor, and to avoid startup congestion. This oil-supply-type compressor includes a main body, an oil-separation device, and an air-discharge passage for discharging compressed air during capacity control of the compressor. The air-discharge passage includes passages having large and small flow volumes, and when compressed air is discharged from the passage to the atmosphere during capacity control, the pressure in the oil-separation device is discharged using the large-flow-volume passage, until the pressure reaches or falls below a restarting-possible pressure, which is the pressure at which startup congestion does not occur when the compressor main body is restarted.

Abstract: The objective of the present invention is to reduce the pressure reduction time while preventing foaming in an oil separation device during capacity control of a compressor, and to avoid startup congestion and thus enable normal starting even when a portion provided in an air release pipe and having a small flow path cross-sectional area becomes clogged. This oil supply type compressor is equipped with a compressor main body, an oil separation device, and an air discharge passage for discharging compressed air during capacity control of the compressor.

Abstract: Provided is an air compressor that can keep good alignment between pulleys 2b and 3b respectively of a compressor body and an electric motor, and a drive belt 4 placed thereacross. Between a base 1 and the electric motor 3, an adjustment mechanism 5 is provided for adjusting the tension of the drive belt 4 by changing the relative position between the compressor body 2 and the electric motor 3. The adjustment mechanism 5 is provided with an electric-motor base 6 for supporting the electric motor, a support unit 7 that supports the electric-motor base 6 to allow a tilting axis thereof to be able to tilt at a position lower of an output shaft of the electric motor, and fixing unit 8 provided between an end of the electric-motor base 6 and the base 1 for fixing the electric-motor base 6 in a tilting state.