A scroll compressor including a center housing; a front housing fastened to the center housing and forming a suction chamber; a rear housing fastened to the center housing and forming a compression mechanism accommodation space. Fixed scroll is in the compression mechanism accommodation space. An orbiting scroll interposes between the center housing and the fixed scroll forming a compression chamber together with the fixed scroll. Fixed scroll may include a fixed scroll end plate and a fixed scroll side plate protruded from outer circumferential portion of fixed scroll end plate, fastened to the center housing, and forming orbiting space of orbiting scroll. Outer circumferential portion of the center housing may be formed with an inflow hole for communicating with the suction chamber. Distal end surface of the fixed scroll side plate is formed with a suction port for guiding the refrigerant of the inflow hole to the compression chamber.

Provided is a hydraulic orbital machine and a method of adjusting a hydraulic orbital machine comprising a first and a second lobed disk which rotate eccentrically about a rotation axis and within respective rotors; the machine is characterized by the fact that it has adjustment means designed to mutually angularly offset the angles at which, when the machine is at a standstill, the chambers defined between the lobed disks and the stator have minimum volume.

Tapered stator designs are engineered in a positive displacement motor (PDM) power section to relieve stator stress concentrations at the lower (downhole) end of the power section in the presence of rotor tilt. A contoured stress relief (i.e. a taper) is provided in the stator to compensate for rotor tilt, where the taper is preferably more aggressive at the lower end of the stator near the bit.

Systems and methods are provided for pumps that deliver optimized torque characteristics and volumetric efficiency. A system includes a housing defining a surface and a rotor defining a face. A face clearance is defined between the face and the surface. The face clearance is variable in magnitude and determinative of target performance characteristics of the pump system. The housing is made of a material selected to have a thermal expansion characteristic and the rotor is made of a second material selected to have another thermal expansion characteristic. The thermal expansion characteristics deliver the target performance characteristics of the pump system.

Systems and methods are provided for pumps that deliver optimized torque characteristics and volumetric efficiency. A system includes a housing defining a surface and a rotor defining a face. A face clearance is defined between the face and the surface. The face clearance is variable in magnitude and determinative of target performance characteristics of the pump system. The housing is made of a material selected to have a thermal expansion characteristic and the rotor is made of a second material selected to have another thermal expansion characteristic. The thermal expansion characteristics deliver the target performance characteristics of the pump system.

A multi-stage vacuum pump comprising a stator defining multiple pumping chambers is discussed. The stator comprises a plurality of transfer channels for providing a fluid passage from an outlet port of one of the plurality of pumping chambers to an inlet port of a subsequent pumping chamber. Some of the transfer channels comprise two side channel sections on opposing sides of the stator. One of the transfer channels comprises a single side channel section on one side of the stator. The vacuum pump further comprises a gas ballast inlet channel arranged on an other side of the stator to the one side of the stator.

A variable hydraulic pump include a rotor mounted on a pump housing of which a housing spring end is formed, a pivot pin, an outer ring rotatably coupled to the pivot pin and of which a ring spring end is formed, a spring mounted between the housing spring end and the ring spring end, a pressure chamber formed in the pump housing to push the outer ring, a plurality of vane provided to form a plurality of pockets, an input port to supply oil to the plurality of pockets and a discharge port to exhaust oil supplied to the plurality of pockets, wherein at the reference position of the outer ring, the angle between a first imaginary line connecting the center of the rotor and the pivot pin and a second imaginary line connecting the ring spring end and the pivot pin is 0 to 10 degrees.

A pump body assembly, fluid machinery, and a heat exchange device. The pump body assembly includes: at least two structure members; a cylinder disposed between the two structure members; and a piston assembly disposed in the cylinder. The piston assembly includes a piston sleeve and a piston slidably disposed in the piston sleeve; an upper end surface of the piston sleeve fits and is limited by a lower end surface of one structure member disposed above the piston sleeve, to prevent the piston sleeve from displacing along a radial direction relative to the one structure member, and effectively solving a problem in prior art that working efficiency of the pump body assembly is affected because the piston sleeve of the pump body assembly is prone to eccentrically rotate.

A split power gerotor pump includes a rotational axis, a shaft, an inner gerotor, an eccentric pocket, and an outer gerotor. The inner gerotor is rotationally fixed on the shaft, rotatable about the rotational axis, and includes n first lobes. The eccentric pocket is rotatable about the rotational axis, and includes a cylindrical bore with a center radially offset from the rotational axis and an outer surface, disposed radially outside of the cylindrical bore and arranged for direct engagement with a gear or a rotor for an electric motor. The outer gerotor includes a cylindrical outer surface installed in the cylindrical bore and n+1 second lobes.

A fluid pump includes a rotor which is centered about an axis, the rotor having a rotor central chamber and a plurality of vane slots. A stator has a recess therein within which the rotor is located, the recess having a recess peripheral surface which is eccentric to the axis. Each vane slot includes a vane therein such that the vanes define a plurality of pumping chambers which expand and contract based on rotational position the rotor relative to the stator. A positioning ring is located within the rotor central chamber such that the positioning ring engages each vane and such that the positioning ring urges each vane into contact with the recess peripheral surface. The positioning ring is radially aligned with a midpoint of each vane.