Abstract: A centrifugal-separation type oil separator includes a cylindrical separator body, and an inflow pipe arranged to introduce a fluid including an oil into the separator body. The inflow pipe includes a curved portion. The curved portion includes at least one oil draining hole.

Abstract: A screw compressor includes a casing having an outer peripheral wall, and a compression mechanism. The compression mechanism includes a screw rotor with helical grooves, a gate rotor with a plurality of gates meshing with the helical grooves, and a cylinder housing the screw rotor. The compression mechanism is disposed inward of the outer peripheral wall. The outer peripheral wall has a discharge passage through which a fluid compressed in the compression mechanism flows. The discharge passage includes an inner peripheral passage formed along an outer peripheral surface of the cylinder, and an outer peripheral passage formed along the inner peripheral passage and the outer peripheral wall. The inner and outer peripheral passages are formed so that the fluid compressed in the compression mechanism sequentially flows through the inner and outer peripheral passages.

Abstract: A screw compressor includes a casing, a motor provided in the casing, a screw rotor inserted into a cylinder in the casing, a bearing holder, a drive shaft, a first bearing, and a second bearing. The cylinder is formed on a lateral side of the motor. The bearing holder is disposed on an opposite side of the screw rotor from the motor and adjacent to the screw rotor. The drive shaft is connected to the motor and the screw rotor. The first bearing is disposed adjacent to the screw rotor. The second bearing is disposed adjacent to the motor in an axial direction of the drive shaft. At least a portion of the first bearing is disposed inside the screw rotor.

Abstract: A screw compressor includes a casing having an outer peripheral wall, and a compression mechanism. The compression mechanism includes a screw rotor with helical grooves, a gate rotor with a plurality of gates meshing with the helical grooves, and a cylinder housing the screw rotor. The compression mechanism is disposed inward of the outer peripheral wall. The outer peripheral wall has a discharge passage through which a fluid compressed in the compression mechanism flows. The discharge passage includes an inner peripheral passage formed along an outer peripheral surface of the cylinder, and an outer peripheral passage formed along the inner peripheral passage and the outer peripheral wall. The inner and outer peripheral passages are formed so that the fluid compressed in the compression mechanism sequentially flows through the inner and outer peripheral passages.

Abstract: A centrifugal-separation type oil separator includes a cylindrical separator body, and an inflow pipe arranged to introduce a fluid including an oil into the separator body. The inflow pipe includes a curved portion. A peripheral wall of the separator body and the inflow pipe include a common portion common to each other.

Abstract: A centrifugal-separation type oil separator includes a cylindrical separator body, and an inflow pipe arranged to introduce a fluid including an oil into the separator body. The inflow pipe includes a curved portion. The curved portion includes at least one oil draining hole.

Abstract: A centrifugal-separation type oil separator includes a cylindrical separator body, and an inflow pipe arranged to introduce a fluid including an oil into the separator body. The inflow pipe includes a curved portion. A peripheral wall of the separator body and the inflow pipe include a common portion common to each other.

Abstract: A screw compressor includes a first rotor provided with a helical groove, a second rotor meshing with the first rotor, and a rotor casing covering at least an outer periphery of the first rotor. The second rotor rotates together with the first rotor. The rotor casing defines a compression chamber in the helical groove together with the first rotor and the second rotor. A fluid is compressible in the compression chamber. At least one of the first rotor or the second rotor is provided with an oil supply passage connected to an oil supply port opened at a sliding surface of the rotor to supply a lubricant to the sliding surface.

Abstract: A screw compressor includes a casing, a motor provided in the casing, a screw rotor inserted into a cylinder in the casing, a bearing holder, a drive shaft, a first bearing, and a second bearing. The cylinder is formed on a lateral side of the motor. The bearing holder is disposed on an opposite side of the screw rotor from the motor and adjacent to the screw rotor. The drive shaft is connected to the motor and the screw rotor. The first bearing is disposed adjacent to the screw rotor. The second bearing is disposed adjacent to the motor in an axial direction of the drive shaft. At least a portion of the first bearing is disposed inside the screw rotor.

Abstract: A screw compressor includes a casing, a drive shaft, a screw rotor, a gate rotor, a slide valve, and a slide valve driving mechanism having a hydropneumatic cylinder. The drive shaft has one end supported via a bearing on a bearing holder held by the casing. The other end is coupled to an electric motor. A compression chamber is defined by the gate rotor meshing with a helical move formed on the screw rotor. The hydropneumatic cylinder is located opposite to the screw rotor with respect to the bearing. The bearing holder has an outer peripheral surface configured as a guide surface guiding a sliding movement of the slide valve. The bearing holder has axial end portions. One of the axial end portions located opposite to the screw rotor constitutes a cylinder tube of the hydropneumatic cylinder to achieve integration of the bearing holder and the hydropneumatic cylinder.

Abstract: A screw compressor includes a casing, a drive shaft, a screw rotor, a gate rotor, a slide valve, and a slide valve driving mechanism having a hydropneumatic cylinder. The drive shaft has one end supported via a bearing on a bearing holder held by the casing. The other end is coupled to an electric motor. A compression chamber is defined by the gate rotor meshing with a helical groove formed on the screw rotor. The hydropneumatic cylinder is located opposite to the screw rotor with respect to the bearing. The bearing holder has an outer peripheral surface configured as a guide surface guiding a sliding movement of the slide valve. The bearing holder has axial end portions. One of the axial end portions located opposite to the screw rotor constitutes a cylinder tube of the hydropneumatic cylinder to achieve integration of the bearing holder and the hydropneumatic cylinder.

Abstract: A screw compressor includes a casing, a screw rotor, an oil sump containing lubricant oil, a lubrication passage and a flow rate controller. The screw rotor is inserted in a cylinder portion of the casing to form a fluid chamber. The screw rotor rotates to suck a fluid into the fluid chamber for compression. The lubrication passage supplies the lubricant oil in the oil sump to the fluid chamber due to a difference in pressure between the oil sump and the fluid chamber. The flow rate controller reduces a flow rate of the lubricant oil supplied to the fluid chamber in accordance with a decrease in operating capacity of the screw compressor.

Abstract: A screw compressor includes a screw rotor having a plurality of helical grooves, a casing containing the screw rotor and a gate rotor. The casing includes a discharge port on an inner peripheral surface of the casing. The gate rotor has gates meshing with the helical grooves of the screw rotor to compress gas in compression chambers to discharge the gas from the discharge port after being compressed. The compression chambers are defined by the helical grooves, the casing, and the gates. The discharge port is divided into a first port and a second port when two adjacent helical grooves of the plurality of helical grooves is open to the discharge port as a result of rotation of the screw rotor, with one of the two adjacent helical grooves being open in the first port and the other of the two adjacent helical grooves being open in the second port.

Abstract: A compressor includes a casing, a screw rotor, a slide member with at least one economizer port, and a control unit controlling a position of the slide member along the axis of the screw rotor to position the at least one economizer port based on the rotating speed of the screw rotor to advance the timing of opening of the at least one economizer port. The controller controls the position of the slide member along the axis such that the slide member moves upstream toward a suction side of the compressor when the rotating speed of the screw rotor increases, and downstream toward a discharge side of the compressor when the rotating speed of the screw rotor decreases. A refrigerating apparatus includes the compressor, a condenser, a heat exchanger, an expansion unit, and an evaporator, sequentially connected, and has an economizer line.

Abstract: A screw compressor includes a screw rotor, a gate rotor and an injection mechanism. The screw rotor is provided with multiple helical grooves. The gate rotor is provided with multiple gates meshing with the helical grooves to form at least one compression chamber between at least one of the helical grooves and at least one of the gates. The compression chamber is configured and arranged such that refrigerant taken-in from a starting-end side of the helical groove is compressed and discharged from a dead-end side of the helical groove. The injection mechanism is configured and arranged to inject oil or refrigerant from a discharge hole of the injection mechanism into the compression chamber such that rotational torque is imparted in a direction in which the screw rotor is rotated at a time of compression.

Abstract: A screw compressor includes a screw rotor, a casing, a low pressure space, a bypass passage and a slide valve. The screw rotor is provided with a plurality of helical grooves forming fluid chambers. The casing includes a cylinder portion with the screw rotor disposed in the cylinder portion. The low pressure space is formed in the casing to receive a flow of uncompressed, low pressure fluid. The bypass passage is opened in an inner peripheral surface of the cylinder portion to communicate the fluid chamber with the low pressure space. The slide valve is slideable in an axial direction of the screw rotor to change an area of an opening of the bypass passage in the inner peripheral surface of the cylinder portion. An end face of the slide valve facing the bypass passage is inclined along an extending direction of the helical grooves.

Abstract: A screw compressor includes a casing, a screw rotor and a gate rotor. The casing has a cylinder. The screw rotor is cylindrical-shaped and configured to be fitted into the cylinder. The gate rotor is configured to be engaged with the screw rotor. A, outlet width of a seal surface of the casing on a gas-outlet side of the screw rotor is larger than an inlet width of the seal surface on a gas-inlet side of the screw rotor. The seal surface of the casing is opposed to one surface of the gate rotor.

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: In a single screw compressor, gates (51) of gate rotors (50) are to be engaged with spiral grooves (41) of a screw rotor (40). In each spiral groove (41) of the screw rotor (40), an area extending from a start point of the spiral groove (41) to a position in a compression stroke is a suction-side portion (45), and the remaining portion (portion up to a terminal point of the spiral groove (41)) is a discharge-side portion (46). In the discharge-side portion (46), a clearance between a wall surface (42, 43, 44) therein and the gate (51) is substantially “0 (zero).” A clearance between the wall surface (42, 43, 44) in the suction-side portion (45) and the gate (51) is wider than that between the wall surface (42, 43, 44) in the discharge-side portion (46) and the gate (51), and is gradually narrowed from the start point toward the terminal point in the spiral groove (41).

Abstract: In a screw rotor (40), a first suction-side area (45) is formed in a first side wall surface (42) of a spiral groove (41). In the first side wall surface (42), a portion extending from a start point to a point until immediately before a compression chamber (23) is in a completely-closed state defines the first suction-side area (45). The first suction-side area (45) is thinner than a portion of the first side wall surface (42) other than the first suction-side area (45), and does not contact a gate (51) of a gate rotor (50).