Abstract: Provided is a multi-stage screw compressor with which an intermediate shaft section of a rotor can be made shorter. A two-stage screw compressor includes a front-stage compressing mechanism 1 which has a front-stage male rotor 11A and a front-stage female rotor 11B, and which compresses air, and a rear-stage compressing mechanism 2 which has a rear-stage male rotor 12A and a rear-stage female rotor 12B, and which further compresses the air compressed by the front-stage compressing mechanism 1. The front-stage male rotor 11A and the rear-stage male rotor 12A are configured to be coaxial, and the front-stage female rotor 11B and the rear-stage female rotor 12B are configured to be coaxial. An axial delivery pocket 34 of the front-stage compressing mechanism 1 and an axial intake pocket 39 of the rear-stage compressing mechanism 2 are arranged in a positional relation of partly overlapping with each other in the axial direction of the rotor, and are separated from each other by a separating wall 41.

Abstract: The invention prevents a decrease in strength of a screw rotor including a hollow portion and improves cooling performance.

Abstract: Provided is a multi-stage screw compressor with which an intermediate shaft section of a rotor can be made shorter. A two-stage screw compressor includes a front-stage compressing mechanism 1 which has a front-stage male rotor 11A and a front-stage female rotor 11B, and which compresses air, and a rear-stage compressing mechanism 2 which has a rear-stage male rotor 12A and a rear-stage female rotor 12B, and which further compresses the air compressed by the front-stage compressing mechanism 1. The front-stage male rotor 11A and the rear-stage male rotor 12A are configured to be coaxial, and the front-stage female rotor 11B and the rear-stage female rotor 12B are configured to be coaxial. An axial delivery pocket 34 of the front-stage compressing mechanism 1 and an axial intake pocket 39 of the rear-stage compressing mechanism 2 are arranged in a positional relation of partly overlapping with each other in the axial direction of the rotor, and are separated from each other by a separating wall 41.

Abstract: The invention prevents a decrease in strength of a screw rotor including a hollow portion and improves cooling performance.

Abstract: Size reduction of a compressor and cooling of an electric motor are effectively achieved. An oilless compressor, having: a compressor main body that has a rotor for compressing air, a rotor shaft for supporting the rotor, and a bearing for rotatably supporting the rotor shaft; an electric motor for producing drive force for driving the compressor main body; at least one gear for transmitting drive force to the rotor shaft; a lubricating oil pipe for conveying lubricating oil to the bearing and/or the gear; and an oil pump for pressure-feeding the lubricating oil; wherein the electric motor has, in the external peripheral direction of an armature, a cooling jacket for channeling the lubricating oil to an internal flow channel to cool the armature of the electric motor, and the lubricating oil circulates through the cooling jacket and the lubricating oil pipe.

Abstract: Size reduction of a compressor and cooling of an electric motor are effectively achieved. An oilless compressor, having: a compressor main body that has a rotor for compressing air, a rotor shaft for supporting the rotor, and a bearing for rotatably supporting the rotor shaft; an electric motor for producing drive force for driving the compressor main body; at least one gear for transmitting drive force to the rotor shaft; a lubricating oil pipe for conveying lubricating oil to the bearing and/or the gear; and an oil pump for pressure-feeding the lubricating oil; wherein the electric motor has, in the external peripheral direction of an armature, a cooling jacket for channeling the lubricating oil to an internal flow channel to cool the armature of the electric motor, and the lubricating oil circulates through the cooling jacket and the lubricating oil pipe.

Abstract: A multistage compressor including: at least a first compressor main body and a second compressor main body configured to suck compressed gas discharged from the first compressor main body to discharge the compressed gas with higher pressure; a first driving source configured to drive the first compressor main body; a second driving source configured to drive the second compressor main body; an intermediate pipe configured to connect a discharge side of the first compressor main body and a suction side of the second compressor main body; a low-pressure side discharge piping system branched from the intermediate pipe; an on-off valve disposed in the low-pressure side discharge piping system and configured to switch permission and prohibition of a flow of compressed gas discharged from the first compressor main body; and a control unit configured to control driving of the first driving source and the second driving source.

Abstract: In a water-supply line for performing water-supply to the rotors and the mechanical seal of a compressor, or in a condensed-water collection line for collecting condensed water of a dryer into the inlet port of the compressor, a water reservoir is provided at a position higher than the water-supply unit of the compressor. Moreover, there are provided a start-time water-supply line and a solenoid valve set up therein. Here, the start-time water-supply line establishes the connection between the lower portion of the water reservoir, and the inlet port of the compressor and the water-supply unit of the mechanical seal.

Abstract: In a water-supply line for performing water-supply to the rotors and the mechanical seal of a compressor, or in a condensed-water collection line for collecting condensed water of a dryer into the inlet port of the compressor, a water reservoir is provided at a position higher than the water-supply unit of the compressor. Moreover, there are provided a start-time water-supply line and a solenoid valve set up therein. Here, the start-time water-supply line establishes the connection between the lower portion of the water reservoir, and the inlet port of the compressor and the water-supply unit of the mechanical seal.

Abstract: A fuel cell stack has an air chamber to which is introduced compressed air that is produced by compressing the atmosphere with a compressor. Energy is recovered from exhaust discharged from the air chamber as it is expanded by an expander. The compressor and the expander are connected to each other via the air chamber of the fuel cell stack through piping. The pressure of the exhaust flowing through the piping is detected by a pressure sensor and, based on the detected pressure, a throttle valve controls a flow rate of the exhaust drawn into the expander.

Abstract: To prevent from fitting into an insertion part of the other leg part or from being deformed on packing and, additionally to strengthen a fixation by soldering, a leg part for fling a connector to a printed board has an elongated hole, and a protrusion or bulging part is provided in long side parts of the elongated hole so that a narrowest space in the elongated hole becomes narrower than a plate thickness of the leg part. The shape of the protrusion or bulging part is formed into a rectangular shape, a triangular shape, a trapezoid shape, a semicircular shape, a semi-elliptic shape, or a combination of two or more among the same shapes.

Abstract: A fuel cell stack has an air chamber to which is introduced compressed air that is produced by compressing the atmosphere with a compressor. Energy is recovered from exhaust discharged from the air chamber as it is expanded by an expander. The compressor and the expander are connected to each other via the air chamber of the fuel cell stack through piping. The pressure of the exhaust flowing through the piping is detected by a pressure sensor and, based on the detected pressure, a throttle valve controls a flow rate of the exhaust drawn into the expander.

Abstract: A compressor has inlet guide vanes, rotor blades and stator blades. To prevent rotating stall, baffle vanes 5 capable of having their angles varied are installed upstream of the inlet guide vanes, actuators to vary the angles of baffle vanes are coupled to the baffle vanes, sensors installed upstream of the baffle vanes detect a rotating stall condition inside the flow passage of the compressor, and a control unit is responsive to signals from the sensors to output control signals to the actuators to vary the angles of the baffle vanes so as to prevent the rotating stall condition. Instead of the baffle vanes, fluid jets may be provided upstream of the inlet guide vanes for the same purposes.