Abstract: A scroll compressor includes a casing, and an internal sealed space in the casing; a drive motor configured with a stator and a rotor which rotates within the stator, and that has an internal flow passage and an external flow passage; a rotation shaft connected to the rotor; a compression unit that includes a first scroll, and a second scroll which is engaged with the first scroll to form a compression chamber, with which the rotation shaft is eccentrically combined; a discharge pipe that communicates with an upper space of the internal space; an oil separation member disposed in the upper space; and a guidance member that is provided between an upper end of the drive motor and a lower end of the discharge pipe and guides the refrigerant with which the oil is mixed, to the oil separation member.

Abstract: An internal gear pump includes an outer rotor, an inner rotor, and a pump housing. The inner rotor is rotatably disposed inside the outer rotor having internal teeth, forms pump chambers between the outer rotor and the inner rotor, and has external teeth. The pump housing has an inhalation port, a discharge port, and a first notch formed within a first land surface that extends from an end of the inhalation port to an end of the discharge port. The first notch is formed along a projection trajectory obtained by projecting a trajectory of chip points on the first land surface, where each chip point is a middle point between a corresponding one of the internal teeth and a corresponding one of the external teeth at a location at which the internal and external teeth substantially face each other above the first land surface and are closest to each other.

Abstract: The present disclosure provides a method for modifying performance of a rotor profile by adjusting meshing line segments, including the following steps: step 1, dividing a meshing line of a bilateral profile into eight functional segments; step 2, constructing each functional segment by using a cubic NURBS curve; and step 3, locally adjusting the functional segments of the meshing line by adjusting control points or weight factors of the NURBS curve, and observing corresponding changes of the rotor profile so as to adjust corresponding geometrical parameters.

Abstract: Variable volume chamber devices are disclosed. The chambers may be defined by the space between two complementary rotors. The volume of the chambers may vary as a function of the variation of relative rotational speeds of the two rotors.

Abstract: A compressor includes a compression chamber forming member, an injection passage, an injection pipe, and a pulsation attenuation space. The compression chamber forming member forms a compression chamber. The injection passage is formed in at least one of the compression chamber forming member and a separate member disposed in a surrounding area and connecting to the compression chamber. The injection pipe supplies refrigerant to the injection passage. The pulsation attenuation space is formed in one of the compression chamber forming member and the separate member disposed in the surrounding area so as to communicate with the injection passage. The pulsation attenuation space attenuates pulsation of refrigerant gas flowing from the injection pipe into the compression chamber.

Abstract: A rotary compressor arrangement is disclosed that includes a body centered at a shaft axis, a cylindrical piston arranged with respect to the body such that an inner volume is created between them, and guiding means arranged at an offset axis with respect to the shaft axis. Also disclosed is a cooling/refrigerant system that includes the rotary compressor arrangement.

Abstract: Volumetric compressor (1) for collection and/or treatment equipment of material in liquid, solid, dusty or muddy form. The compressor (1) comprises an operative chamber (50), defining a suction section and an exhaust section of a first fluid, a first header (61) and a second header (62), which delimit said chamber (50) on opposite parts along a longitudinal axis (101). The compressor further comprises at least two rotors (80?, 80?) with lobes (81?, 81?) housed in the chamber (50), each rotor (80?, 80?) rotating about a rotation axis (108?, 108?) substantially parallel to said longitudinal axis (101). The lobes of each rotor develop according to a helical profile. Furthermore, each of the headers (61,62) defines at least one injection opening (71?, 71?,72?,72?) communicating with a feeding device (150) of a second fluid.

Abstract: An epitrochoidal vacuum pump includes a housing having a chamber, a rotor rotatably received within the internal space of the chamber, and a drive shaft configured to rotate the rotor eccentrically about an axis within the chamber in an epitrochoidal manner. An externally toothed guide sprocket meshes with and guides movement of a guide gear of the rotor as it is driven by the drive shaft. A chamber inlet draws air under negative pressure into the housing, and an outlet is provided to expulse air under positive pressure from the housing. Further, a fluid inlet is provided to input lubricant along the drive shaft and into the internal space of the chamber. The fluid inlet is communicated by channel(s) in an interior of the housing. The lubricant is drawn into the housing via a pressure differential.

Abstract: A scroll compressor formed having a casing, a compression unit provided in an inner space of the casing to form a compression chamber composed of an inner pocket and an outer pocket by a pair of two scrolls, and bypass holes provided in the compression unit to bypass refrigerant suctioned into the compression chamber to the inner space of the casing to vary compression capacity, wherein the bypass holes are formed in a compression chamber constituting the inner pocket and a compression chamber constituting an outer pocket to be located in compression chambers having different pressures along a movement path of the respective compression chambers.

Abstract: A scroll compressor includes a first scroll member, a second scroll member, and an aerostatic thrust bearing. The aerostatic thrust bearing forms a layer of gas between the second scroll member and a fixed supporting member to support the second scroll member as the second scroll member rotates and/or orbits. Also disclosed is a method of supporting a rotating/orbiting scroll member in a scroll compressor. The method including supplying pressurized gas to an aerostatic thrust bearing such that a layer of gas is formed between the rotating/orbiting scroll member and a fixed supporting member.

Abstract: A casing of a housing of a fuel pump has a bearing surface that rotatably supports an inner gear in an axial direction from a motor side while a plain bearing extends through the bearing surface. The plain bearing includes: an inner-peripheral-side step that is stepped by increasing an inner diameter of the plain bearing on a counter-motor side of the inner-peripheral-side step in the axial direction; and an outer-peripheral-side step that is stepped by increasing an outer diameter of the plain bearing on the motor side of the outer-peripheral-side step at a position that is on the motor side of the bearing surface in the axial direction.

Abstract: A bearing housing drain in a scroll compressor and method for controlling lubrication of a thrust bearing in the scroll compressor are disclosed. The compressor includes a compressor housing; a non-orbiting scroll member and an orbiting scroll member; an orbiting scroll hub having an upper end and a lower end, the lower end being disposed at a vertical elevation that is lower than the upper end; a thrust bearing; a lubricant sump; a housing drain cavity disposed within the compressor housing and configured to receive lubricant from the lubricant sump and to deliver the lubricant to the thrust bearing; and a bearing housing drain fluidly connected to the housing drain cavity and the lubricant sump.

Abstract: The present disclosure is directed to a screw compressor system having a compressor housing with a pair of screw rotors rotatably supported within a compression chamber. A lubricant port is in fluid communication with the compression chamber. A nozzle insert having a longitudinal body extending between a first end and a second end can be positioned within the lubricant port. A swirl chamber formed by the nozzle insert or tangential flow into an offset lubricant port is configured to generate an atomized lubricant flow and discharge the atomized lubricant into the compression chamber.

Abstract: A rotary machine, for directing a quantity of fluid from an inlet to an outlet, comprises one or more elliptical or near-elliptical rotors having planetary rotation within a housing. The interior cavity of the housing comprises an inverse apex region that is in contact with the rotor during its rotation. In various embodiments the rotor and housing can be symmetric or asymmetric in cross-section. Features are described that can improve the operation of the machine for various end-use applications. Such features include cut-outs that are fluidly connected to the inlet or outlet ports of the machine, mechanisms for reducing variation in output flow rate from the rotary machine, linings for the interior cavity of the housing, pressure relief mechanisms, dynamic apex seals and other sealing mechanisms.

Abstract: Sealing in rotary positive displacement machines based on trochoidal geometry that comprise a helical rotor that undergoes planetary motion within a helical stator is described. Seals can be mounted on the rotor, the stator, or both. The rotor can have a hypotrochoidal cross-section, with the corresponding stator cavity profile being the outer envelope of the rotor as it undergoes planetary motion, or the stator cavity can have an epitrochoidal cross-section with the corresponding rotor profile being the inner envelope of the trochoid as it undergoes planetary motion. In some embodiments, the geometry is offset in a manner that provides advantages with respect to sealing in the rotary machine. In multi-stage embodiments, the rotor-stator geometry remains substantially constant or varies along the axis of the rotary machine.

Abstract: Rotary positive displacement machines based on trochoidal geometry, that comprise a helical rotor that undergoes planetary motion within a helical stator are described. The rotor can have a hypotrochoidal cross-section, with the corresponding stator cavity profile being the outer envelope of the rotor as it undergoes planetary motion, or the stator cavity can have an epitrochoidal cross-section with the corresponding rotor profile being the inner envelope of the trochoid as it undergoes planetary motion. In some embodiments, the geometry is offset in a manner that provides structural and/or operational advantages in the rotary machine.

Abstract: A variable oil pump includes a pump rotor housed in a housing and rotationally driven, an adjustment ring that adjusts an amount of oil discharged from the pump rotor by being displaced under hydraulic pressure supplied to a hydraulic chamber between the housing and the pump rotor in a state where the pump rotor is rotatably held from an outer peripheral side, and a vane provided in a portion where the adjustment ring and the housing face each other and that seals oil leakage to an outside of the hydraulic chamber. The adjustment ring includes a vane holding portion that holds the vane and an oil passage through which the hydraulic pressure in the hydraulic chamber is drawn into the vane holding portion.

Abstract: [Object] To efficiently supply lubricant oil to a bearing member with a simple mechanism. [Solving Means] A vacuum pump includes a first housing, a second housing, a rotor shaft, a lubricant oil-stirring plate, and a bearing member. The second housing is attached to the first housing and forms a space that stores lubricant oil together with the first housing. The rotor shaft passes through the first housing. The lubricant oil-stirring plate is housed in the space and is attached to the rotor shaft. The bearing member is fixed to the first housing and rotatably supports the rotor shaft. The first housing includes a supply port that enables lubricant oil to be supplied to the bearing member. The second housing includes an inner-wall upper portion which the lubricant oil stirred by the lubricant oil-stirring plate hits against. The inner-wall upper portion of the second housing includes a recess portion that enables the lubricant oil to move above the supply port.

Abstract: A scroll compressor with a first valve having a first surface to open/close between a first path and a second path; a back pressure chamber assembly or non-orbiting scroll having a third path through which a first pressure refrigerant flows, a fourth path through which refrigerant of a second pressure lower than the first pressure flows, and one end in communication with the third and fourth paths and the other end having a fifth path in communication with a second surface of the first valve; and a second valve provided where the third, fourth, and fifth paths meet and moveable between first and second positions, wherein at the first position the third and fifth paths communicate to supply the first pressure refrigerant toward the second surface, and at the second position the fourth and fifth paths communicate to supply the second pressure refrigerant toward the second surface.

Abstract: A scroll compressor including a casing; a compression unit provided in an inner space of the casing to form a compression chamber by a pair of two scrolls; a bypass hole provided in the compression unit to bypass refrigerant suctioned into the compression chamber to the inner space of the casing; a bypass valve configured to selectively open and close the bypass hole to vary a compression capacity of the compression chamber; a back pressure chamber provided on a rear side of either one of the pair of two scrolls to support the scroll in the other scroll direction; a back pressure passage configured to communicate between the compression chamber and the back pressure chamber; and a back pressure valve configured to selectively open and close the back pressure passage.