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.

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 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: 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: The present invention relates to a novel hybrid anode configuration for a radiation detector that effectively reduces the edge effect of surface defects on the internal electric field in compound semiconductor detectors by focusing the internal electric field of the detector and redirecting drifting carriers away from the side surfaces of the semiconductor toward the collection electrode(s).

Abstract: The present invention provides a screw compressor wherein, even if a gate rotor flexes owing to a temperature differential between a casing and a screw rotor during operation of a compressor, the gate rotor is prevented, with a simple configuration, from biting into the screw rotor, which reduces the amount of wear of the gate rotor and prevents a decline in the compressor's performance. The gate rotor (3) comprises a gate rotor main body (30) and a shaft (40) to which the gate rotor main body (30) is attached. An elastic body (5) is disposed between (S) the axle (41) of the shaft (40) and the hole (32) of the gate rotor main body (30).

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 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 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 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 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: In an acoustic fluid machine, an acoustic resonator gradually reduces in diameter towards the top on which a valve device is provided to suck a gas into the resonator. The gas is compressed in the resonator by a circular-plate piston at the lower end of the resonator and discharged via an outlet of the valve device. The piston comprises a rubber plate fixed to the resonator and a metal plate attached on the rubber plate.

Abstract: In an acoustic resonator, an actuator allows a piston to reciprocate axially at very small amplitude at high speed. Owing to pressure fluctuation in the acoustic resonator involved by reciprocal motion of the piston, fluid is sucked into and discharged from the acoustic resonator via a valve device at the top end of the acoustic resonator. The acoustic resonator is covered with a gas guide with a space. The valve device is cooled by a fan at the top end of the gas guide.

Abstract: A resonator of an acoustic compressor is provided at each side of an actuator so that the two resonators are arranged side by side. Two pistons are provided at the inner ends of the resonators and actuated by the actuator. At the outer end of the each of the resonators, a gas is introduced into the resonator through a suction hole. When the pistons are actuated by the actuator, the gases in the two resonators are oscillated and compressed by the piston and discharged through discharge holes at the outer ends of the resonators.

Abstract: A piston is reciprocated axially at high speed at very small amplitude by an actuator in the larger-diameter base of an acoustic resonator. According to pressure fluctuation in the acoustic resonator involved by reciprocal motion of the piston, fluid is sucked into and discharged from the acoustic resonator via a valve device at the top end of the acoustic resonator. The acoustic resonator is contained in a gas guide. Fluid from the valve device is introduced into the gas guide to cool the valve device.

Abstract: In an acoustic fluid machine, an acoustic resonator gradually reduces in diameter towards the top on which a valve device is provided to suck a gas into the resonator. The gas is compressed in the resonator by a circular-plate piston at the lower end of the resonator and discharged via an outlet of the valve device. The piston comprises a rubber plate fixed to the resonator and a metal plate attached on the rubber plate.

Abstract: The present invention is directed to nucleic acid sequences encoding a novel regulatory element that induces a high level of expression to operably linked genes, upon exposure to hypoxic conditions. Furthermore, the regulatory element can be used to prepare an expression vector for transforming plant cells, wherein the DNA construct comprises a hypoxia inducible promoter operably linked to a gene sequence.