A scroll compressor is provided that may include a casing; a drive motor provided at an inner space of the casing; a rotational shaft coupled to a rotor of the drive motor, and rotated together with the rotor; a frame provided below the drive motor; a fixed scroll provided below the frame, and having a fixed wrap; and an orbiting scroll provided between the frame and the fixed scroll, having an orbiting wrap so as to form a compression chamber including a suction chamber, an intermediate pressure chamber, and a discharge chamber, by being engaged with the fixed wrap. In a state in which a center of the fixed scroll and a center of the orbiting scroll are substantially the same, an interval between the fixed wrap and the orbiting wrap gradually increases towards the suction chamber from the discharge chamber.

A scroll compressor is provided that may include an orbiting scroll having an orbiting wrap, and which performs an orbiting motion; and a fixed scroll having a fixed wrap to form a compression chamber including a suction chamber, an intermediate pressure chamber, and a discharge chamber, by being engaged with the orbiting wrap. A wrap thickness of the fixed wrap may be greater than a wrap thickness of the orbiting wrap within a range which forms the suction chamber. With such a configuration, even if the fixed scroll or the orbiting scroll is thermally-expanded, a transformation of the fixed wrap at a suction side may be prevented. This may prevent a gap between the fixed wrap and the orbiting wrap at an opposite side to the suction side, thereby enhancing compression efficiency.

To provide a displacement pump that can be assembled while properly maintaining side clearances. The displacement pump (100, 101, 102, 103, 104, 105) of the present invention for sucking and discharging a fluid such as gasoline vapor by changing pressure in a space constituted by an outer peripheral surface of a rotor (1) and an inner wall surface of a casing (2), comprising a side clearance adjusting member (4), rotating with respect to the pump main body (6), for moving a shaft (3) integrally formed with the rotor (1) in an axial direction of the shaft (3).

A single-screw compressor includes a screw rotor with a helical groove, a cylindrical wall rotatably housing the screw rotor, a gap adjuster mechanism, and a gear-shaped gate rotor having a plurality of flat gates. The gate rotor is arranged outside the wall. Some of the gates enter a space inside the wall via an opening formed in the cylindrical wall and mesh with the screw rotor. A fluid is compressed in a compression chamber defined in the helical move by the screw rotor, the gates meshing with the screw rotor, and the wall. The gap adjuster mechanism avoids contact between a front surface of the gate rotor toward the compression chamber and a sealing surface of the wall facing the front surface, by displacing at least one of the gate rotor and the sealing surface of the wall in an axial direction of the gate rotor.

A scroll compressor is provided that may include an orbiting scroll having an orbiting wrap, and which performs an orbiting motion; and a fixed scroll having a fixed wrap to form a compression chamber including a suction chamber, an intermediate pressure chamber, and a discharge chamber, by being engaged with the orbiting wrap. A wrap thickness of the fixed wrap may be greater than a wrap thickness of the orbiting wrap within a range which forms the suction chamber. With such a configuration, even if the fixed scroll or the orbiting scroll is thermally-expanded, a transformation of the fixed wrap at a suction side may be prevented. This may prevent a gap between the fixed wrap and the orbiting wrap at an opposite side to the suction side, thereby enhancing compression efficiency.

a screw pump including a pump housing in which a pump spindle is rotatably mounted with the involvement of a hydrostatic thrust bearing for absorbing the axial thrust which is produced at the spindle during operation, the hydrostatic thrust bearing being formed by a housing-fixed bearing surface, against which an end-face, spindle-fixed bearing surface of the pump spindle is indirectly supported, by virtue of the fact that the housing-fixed bearing surface and the spindle-fixed bearing surface form a bearing gap therebetween, which bearing gap is fed, in its central region, with a pressure fluid which flows out through the bearing gap in the radial direction, preferably into the intake region, and the hydrostatic pressure of which counteracts the axial thrust.

A uniaxial eccentric screw pump includes: a stator 8 having a through hole 8a whose inner surface is formed in a female screw shape; a rotor 14 that is a male screw shaft body inserted into the through hole 8a of the stator 8; a plurality of shims 9 that are arranged on a radially outside of the stator 8 in a range from one end to the other end of the stator 8, are in surface contact with an outer surface of the stator 8, are capable of compressing the stator 8 by moving radially inward with respect to the stator 8, and have, on an outer surface, an inclined surface 18 gradually inclined radially inward or outward toward one end; and an adjustment member 10 that is movable in an axial direction with respect to the stator 8 and has a pressing part 26 that can press the inclined surface 18 of each of the shims 9.

An improved screw pump such as, for example, a twin screw pump is disclosed. In one embodiment, the screw pump includes a casing, first and second intermeshing rotors, and a liner positioned between the first and second rotors and the casing. In use, the liner is arranged and configured to bend and/or pivot in unison with the first and second rotors under the axial hydraulic pressure experienced by the screw pump during use. In one embodiment, the liner may be arranged and configured to include an asymmetric axial stiffness to facilitate bending of the liner. In another embodiment, the liner may be arranged and configured in multiple segments, the segments being arranged and configured to pivot to approximate the bending of the rotor shafts.

A displacement pump is configured to allow for assembly while properly maintaining side clearances. The displacement pump (100, 101, 102, 103, 104, 105) for sucking and discharging a fluid such as gasoline vapor by changing pressure in a space constituted by an outer peripheral surface of a rotor (1) and an inner wall surface of a casing (2), includes a side clearance adjusting member (4), rotating with respect to the pump main body (6), for moving a shaft (3) integrally formed with the rotor (1) in an axial direction of the shaft (3).

An electric oil pump includes a motor unit having a shaft and a pump unit which is disposed on a front side of the motor unit, is driven by the shaft, and discharges oil. The motor unit includes a rotor, a stator, and a resin housing in which the rotor and the stator are housed. The pump unit includes a pump rotor provided at the shaft and a pump housing having a housing part in which the pump rotor is housed. The pump housing includes the pump body that is supported by the shaft via a sliding bearing and a pump cover that covers a front side of the pump body. A rear side of the shaft is supported by the resin housing via a rolling bearing and a front side of the shaft that protrudes from the motor unit is supported by a pump body via the sliding bearing.