Abstract: A screw compressor includes a rotatable screw rotor and a plurality of gate rotors. The screw rotor has helical grooves formed in an outer circumferential surface of the screw rotor. The gate rotors have a plurality of radially disposed teeth meshing with the grooves of the screw rotor. The helical grooves include a first screw groove and a second screw groove. The first screw groove compresses a fluid from one end side of the screw rotor to an other end side of the screw rotor. The second screw groove compresses the fluid from the other end side of the screw rotor to the one end side of the screw rotor.

Abstract: In a compression mechanism of a rotary compressor, a cylinder chamber is defined by a cylinder and a second housing. A back surface side gap is defined between an end plate part of the cylinder and a flat plate part of a first housing. The first housing is provided with a communicating path and a differential pressure regulating valve. When the difference between the suction pressure and the discharge pressure is small, the discharge pressure is introduced through the communicating path to an intermediate gap whereby both an internal gap and the intermediate gap are placed at the same pressure as the discharge pressure. Conversely, when the difference between the discharge pressure and the suction pressure is great, the communicating path is made discontinuous by the differential pressure regulating valve whereby the intermediate gap is placed at an intermediate pressure lower than the discharge pressure.

Abstract: A refrigeration system includes a first refrigerant passage, a ?-type silencer, and a second refrigerant passage. The ?-type silencer has a first silencing space, a second silencing space, and a communication path. The first silencing space communicates with the first refrigerant passage. The second silencing space is disposed below the first silencing space. The communication path extends from the lower end of the first silencing space to the outside of the first silencing space and communicates with the second silencing space. The second refrigerant passage extends from the lower end of the second silencing space.

Abstract: A single screw compressor structure includes a screw rotor and a casing. The screw rotor has a plurality of helical grooves formed in an outer peripheral surface thereof. The a casing houses the screw rotor. The screw rotor includes a main tapered portion having a tapered outer diameter that becomes larger from an intake side toward a discharge side of the screw rotor, and a reversely tapered portion that is located on a downstream side of a maximum outer diameter portion of the outer surface and on the discharge side of the main tapered portion. The reversely tapered portion has a reversely tapered outer diameter that becomes smaller as the reversely tapered portion extends away from the maximum outer diameter portion.

Abstract: A valve guard for restricting the amount of deformation of a valve disc has a main body part abuttable with the back surface of the valve disc, and a fixation part extending to outside of a receding part. Upon mounting the valve guard to an end plate part, the fixation part is firmly attached to the outside of the receding part of the end plate part.

Abstract: A sealing ring is provided between an end plate of an eccentric rotation body and a support plate so that a pressure of fluid at high pressure is allowed to work on the end plate, thereby allowing an axial-direction pressing force to work on the end plate. The sealing ring is arranged eccentrically away from a center of a cylinder as forming the eccentric rotation body to minimize separation of the axial-direction pressing force from a thrust load in a radial direction in the end plate thereby reducing turnover moment effectively.

Abstract: A reed valve and a valve retainer for the reed valve are provided at a discharge port of a compression mechanism that compresses fluid. The valve retainer has a polymer actuator at an end part of a valve fixing part for fixing the reed valve. The polymer actuator expands or contracts in length to change a fixed length of the reed valve, thereby changing a rigidity of the reed valve. This attains appropriate control of responsiveness of the reed valve according to the volume.

Abstract: An enclosed compressor includes a compression element configured to compress a working fluid, a casing and a fixing member. The casing has a substantially cylindrical shell plate and houses the compression element. The fixing member is welded to the shell plate. The compression element is fixed to the fixing member, wherein fixing of the compression by at least six fastening bolts.

Abstract: A single screw compressor structure includes a screw rotor and a casing, which houses the screw rotor. A tapered outer circumferential surface of the screw rotor has a plurality of helical grooves, with an outer diameter that increases from an inlet side toward a discharge side. The casing includes an outer tube member having a circular inner hole to form an interior, and an inner tube member is fixed to the interior of the outer tube member. The inner tube member has a tapered inner surface that opposes the tapered outer circumferential surface of the screw rotor. A single screw compressor further including a gate rotor is assembled mesh between the screw rotor and the gate rotor, aligning the tapered outer and inner circumferential surfaces relative to one another, and integrally coupling the outer and inner tube members to each other.

Abstract: An air conditioning apparatus is provided whereby the pressure pulsation generated by a compressor can be entirely reduced both during cooling and during heating, and a muffler can be shared. The air conditioning apparatus has a refrigerant circuit. The refrigerant circuit is configured so that a compressor for compressing a refrigerant, an indoor heat exchanger, an outdoor heat exchanger, and a four-way switch valve are connected via a refrigerant pipe. The four-way switch valve switches the flow of refrigerant compressed by the compressor to either the indoor heat exchanger or the outdoor heat exchanger. The air conditioning apparatus further includes a pressure pulsation reducing component. The pressure pulsation reducing component is provided between the four-way switch valve and the indoor heat exchanger. The pressure pulsation reducing component reduces pressure pulsation inside the refrigerant circuit. The pressure pulsation is generated by the compressor.

Abstract: A bolt hole receiving a fixing bolt is formed in a portion of an end plate overlapping an annular piston or a fixed wrap as viewed in a thickness direction of the end plate to open at the back face of the end plate. In fixing a discharge valve to the end plate, the fixing bolt is screwed into the bolt hole.

Abstract: A hermetic compressor is disposed with an annular motor stator, a motor rotor, a casing and plural spot joining portions. The motor rotor is disposed such that it may freely rotate in a space inside the motor stator. The casing includes a cylindrical portion. The cylindrical portion houses the motor stator and the motor rotor. The plural spot joining portions fix the motor stator to the cylindrical portion by spot joining in a state where a clearance is secured between the motor stator and the cylindrical portion.

Abstract: A blade moves backward/forward to enter four different states, namely a first state in which the tip thereof is in sliding contact with the internal peripheral surface of an external side cylinder part, a second state in which the tip is positioned in the cutaway portion of a ring-shaped piston to thereby place only an external side cylinder chamber at rest, a third state in which the tip is positioned in the cutaway portion of an internal side cylinder part to thereby place only the external side cylinder chamber and an intermediate cylinder chamber at rest, and a whole rest state in which the tip is positioned in a blade groove to thereby place all of the cylinder chambers at rest.

Abstract: A rotary compressor includes a compression mechanism, an electric motor and a controller. The compression mechanism includes a piston and a cylinder having two cylinder chambers. The electric motor is configured to change volumes of the cylinder chambers by eccentrically moving the cylinder and the piston relative to each other. The controller is configured to change an output torque of the electric motor in accordance with a variation in a load torque of the compression mechanism in one turn of rotation.

Abstract: A rotary fluid machinery includes a fixed member, a drive shaft driven and rotated about a rotation axis, a movable member, a movable member support part and a reverse moment generating mechanism. The movable member is rotatably mounted at the drive shaft with its center being eccentrically disposed relative to the rotation axis, with the movable member and the fixed member forming a fluid chamber. Revolution of the movable member changes the volume of the fluid chamber. The movable member is configured to swing in association with its revolution. The reverse moment generating mechanism generates a moment in a reverse direction about the rotation axis relative to a moment about the rotation axis caused by the revolving movement of the movable member.

Abstract: A compressor slider has a carbon content of 2.0 wt % to 2.7 wt %, a silicon content of 1.0 wt % to 3.0 wt %, a balance of iron that includes unavoidable impurities, graphite that is smaller than the flake graphite of flake graphite cast iron, and a hardness that is greater than HRB 90 but less than HRB 100 in at least a portion of the slider.

Abstract: A bolt hole receiving a fixing bolt is formed in a portion of an end plate overlapping an annular piston or a fixed wrap as viewed in a thickness direction of the end plate to open at the back face of the end plate. In fixing a discharge valve to the end plate, the fixing bolt is screwed into the bolt hole.

Abstract: A rotary compressor includes a compression mechanism in which a piston is disposed inside a cylinder chamber of a cylinder. The cylinder and the piston eccentrically rotate relative to each other. The cylinder chamber is sectioned into a high pressure chamber and a low pressure chamber in order to prevent production of vibration and noises due to pressure pulsation caused in a suction process. A low pressure space communicating with a suction side of the compression mechanism and a high pressure space communicating with a discharge side of the compression mechanism are formed in the casing. A suction pipe communicating with the high pressure space and a discharge pipe communicating with the high pressure space are disposed in the casing.

Abstract: A rotary compressor includes a fixed side and a movable side that is eccentrically movable relative to the fixed side. The movable side moves in response to operation of a drive mechanism, which rotates a drive shaft. The fixed side has a main bearing formed as a unitary part. A cylinder may serve as the movable side, which is coupled through an eccentric part to the drive shaft. The drive shaft is supported by the main bearing. With such an arrangement, a ring-shaped piston may serve as the fixed side, which is formed integrally with the main bearing in a front head.

Abstract: A rotary fluid device includes a cylinder having an annular cylinder chamber and an annular piston, which is disposed in the cylinder chamber to be eccentric relative to the cylinder. The annular piston divides the cylinder chamber into an outer working chamber and an inner working chamber. A blade is disposed in the cylinder chamber to partition each of the working chambers into a high-pressure space and a low-pressure space. The cylinder and the piston relatively rotate. The outer working chamber constitutes a compression chamber which compresses and discharges a sucked fluid with the progress of the relative rotation of the cylinder and the piston. The inner working chamber constitutes an expansion chamber which expands and discharges a sucked fluid with the progress of the relative rotation of the cylinder and the piston.