Abstract: In a single screw compressor, gates of a gate rotor mesh with helical grooves of the screw rotor in a casing. The casing has a low pressure space, and a divider wall covering the outer peripheral surface of the screw rotor to divide the fluid chamber formed by the helical groove from the low pressure space. An inlet is formed in the divider wall to partially expose the outer peripheral surface of the screw rotor to the low pressure space. The fluid chamber in a suction phase into which the low pressure fluid flows from the low pressure space is divided from the low pressure space by the gate entering the helical groove after the helical groove has moved from a position where the helical groove faces the inlet to a position where the helical groove is covered with the divider wall.

Abstract: A screw compressor includes a casing having low and high pressure spaces, a screw rotor inserted in a cylinder part of the casing, and a slide valve disclosed in the cylinder part. The screw rotor has a plurality of helical grooves forming a compression chamber. The slide valve is moveable along an axis of the screw rotor and faces an outer periphery of the screw rotor to form a discharge port to communicating the compression chamber with the high pressure space. Fluid in the low pressure space is sucked into the compression chamber, compressed, and then discharged to the high-pressure space when the screw rotor rotates. The slide valve includes a sealing projection located on a back surface of the slide valve opposite to the screw rotor, and separating the low and high pressure spaces from each other when the sealing projection is in slidable contact with the casing.

Abstract: A screw compressor includes a screw rotor, a casing and an economizer circuit. The screw rotor has a plurality of helical grooves forming a compression chamber. The casing has a cylinder portion with the screw rotor inserted in the cylinder portion. The economizer circuit ejects configured to eject intermediate pressure refrigerant into a compression chamber in the course of compression. The economizer circuit includes a branch passage configured to branch the intermediate pressure refrigerant from a portion of a refrigerant circuit, a resonance space connected to a downstream side of the branch passage to retain the intermediate pressure refrigerant, and a resonance passage having an end communicating with an interior of the compression chamber and an other end communicating with an interior of the resonance space. The refrigerant circuit circulates refrigerant and performs a refrigeration cycle.

Abstract: A single-screw compressor includes a screw rotor, a cylinder wall in which the screw rotor is rotatably accommodated, a driving mechanism which variably drives the screw rotor according to a load, and a slide valve which is provided in a slide groove formed in the cylinder wall. The slide valve faces an outer circumferential surface of the screw rotor to be movable in an axial direction, and to adjust a discharge start position by being moved in the axial direction according to the operating capacity. A discharge side end surface of the slide valve extends in a direction corresponding to a screw land of the screw rotor to which the discharge side end surface faces when the slide valve is moved to a position corresponding to a part load operation state.

Abstract: A scroll compressor includes a pressing mechanism and a back-flow prevention mechanism. The pressing mechanism includes a back-pressure chamber facing a back surface of a movable-scroll end plate, and a back-pressure supply path arranged to allow the back-pressure chamber to communicate with a compression chamber which is in a state right before the compression chamber communicates with an outlet port or a state in which the compression chamber communicates with the outlet port. The back-flow prevention mechanism allows refrigerant of the back-pressure supply path to flow from the compression chamber to the back-pressure chamber, and prevents fluid of the back-pressure supply path from returning from the back-pressure chamber to the compression chamber.

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: A scroll compressor includes a stationary scroll and a movable scroll. Each scroll has a helical lap provided on one surface of an individual panel. The laps are brought together to form a compression chamber between the laps. A back pressure chamber is formed in a side of the panel of the movable scroll that is opposite of a side where the lap is formed. At least one concave part capable of communicating with the compression chamber is formed in the surface of the panel of the stationary scroll where the lap is formed. At least one throughhole is formed in the panel of the movable scroll. The throughhole is formed through a thickness direction of the panel of the movable scroll and is configured to intermittently cause the concave part and the back pressure chamber to communicate.

Abstract: A screw compressor includes a screw rotor, a gate rotor, a drive mechanism to rotate the screw rotor, a cylinder, a discharge port and an adjustment mechanism. The screw rotor has an outer periphery with a helical groove engaged with radially arranged gates of the gate rotor. First and second axial ends of the screw rotor form suction and discharge sides, respectively. The cylinder accommodates the screw rotor to define a compression chamber in the helical groove. Fluid in the compression chamber flows through the discharge port toward the discharge side of the screw rotor. The adjustment mechanism is configured to adjust a compression ratio of the compression chamber within a predetermined range. The adjustment mechanism adjusts the compression ratio to a minimum compression ratio immediately before or when operation of the adjustment mechanism is stopped.

Abstract: An airtight compressor includes a compression mechanism disposed inside an airtight container in a position below a gas retention space. An oil supply passage supplies oil from an oil reservoir both to the gas retention space (14) and to a sliding portion of the compression mechanism in a compression space. The oil supply passage communicates the gas retention space with a second space located on an opposite side of the piston from the intake chamber. A second channel is a channel that is different from the oil supply passage. The second channel enables a gas medium to flow from the gas retention space to the second space. Preferably, passage resistance when the gas medium flows through the second channel is less than when the gas medium flows through the oil supply passage.

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 by at least six fastening bolts.

Abstract: A single-screw compressor includes a casing, a screw rotor accommodated in the casing, a gate rotor, and a gate rotor supporting member rotatably supporting the gate rotor. The gate rotor includes a plurality of flat-plate-shaped gates formed in a radial pattern and meshing with a helical groove of the screw rotor. Fluid in a compression chamber defined by the screw rotor, the casing and the gates is compressed when the screw rotor is rotated. The gate rotor supporting member includes a gate supporting portion supporting each gate from a back surface side. The gate rotor and the gate rotor supporting member form a gate rotor assembly including a pressure introduction channel configured and arranged to introduce a fluid pressure on a front surface side of each gate into a gap between a back surface of the gate and the gate supporting portion.

Abstract: A screw compressor includes a screw rotor, a casing and an economizer circuit. The screw rotor has a plurality of helical grooves forming a compression chamber. The casing has a cylinder portion with the screw rotor inserted in the cylinder portion. The economizer circuit ejects configured to eject intermediate pressure refrigerant into a compression chamber in the course of compression. The economizer circuit includes a branch passage configured to branch the intermediate pressure refrigerant from a portion of a refrigerant circuit, a resonance space connected to a downstream side of the branch passage to retain the intermediate pressure refrigerant, and a resonance passage having an end communicating with an interior of the compression chamber and an other end communicating with an interior of the resonance space. The refrigerant circuit circulates refrigerant and performs a refrigeration cycle.

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 by adjusting 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: A screw compressor includes a casing having low and high pressure spaces, a screw rotor inserted in a cylinder part of the casing, and a slide valve disclosed in the cylinder part. The screw rotor has a plurality of helical grooves forming a compression chamber. The slide valve is moveable along an axis of the screw rotor and faces an outer periphery of the screw rotor to form a discharge port to communicating the compression chamber with the high pressure space. Fluid in the low pressure space is sucked into the compression chamber, compressed, and then discharged to the high-pressure space when the screw rotor rotates. The slide valve includes a sealing projection located on a back surface of the slide valve opposite to the screw rotor, and separating the low and high pressure spaces from each other when the sealing projection is in slidable contact with the casing.

Abstract: A screw compressor comprises a first meshing body and a second meshing body. The first meshing body has plural helical flutes disposed around a first rotating shaft. The second meshing body has plural projections or lobes disposed around a second rotating shaft. At least one of the projections or lobes is arranged non-uniformly with respect to the other projections or lobes in a circumferential direction of the second rotating shaft. The plural helical flutes are arranged to be meshable with the plural projections or lobes, in a circumferential direction of the first rotating shaft.

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 screw compressor includes a casing, a screw rotor disposed in a cylinder portion of the casing to define a compression chamber, and a capacity control slide valve. Fluid sucked into the compression chamber is compressed by rotation of the screw rotor. The slide valve is slidable along a rotation axis of the screw rotor and is opposed to an outer circumferential surface of the screw rotor. The slide valve includes a dynamic pressure generator formed on an opposed surface of the slide valve that is opposed to the screw rotor to generate a dynamic pressure using fluid in contact with the opposed surface of the slide valve. The slide valve is configured so that the dynamic pressure generated by the dynamic pressure generator avoids contact between the slide valve and the screw rotor.

Abstract: A screw compressor includes a screw rotor, a gate rotor, a drive mechanism to rotate the screw rotor, a cylinder, a discharge port and an adjustment mechanism. The screw rotor has an outer periphery with a helical groove engaged with radially arranged gates of the gate rotor. First and second axial ends of the screw rotor form suction and discharge sides, respectively. The cylinder accommodates the screw rotor to define a compression chamber in the helical groove. Fluid in the coin cession chamber flows through the discharge port toward the discharge side of the screw rotor. The adjustment mechanism is configured to adjust a compression ratio of the compression chamber within a predetermined. range. The adjustment mechanism adjusts the compression ratio to a minimum compression ratio immediately before or when operation of the adjustment mechanism is stopped.

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 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.