An external rotor pump, in particular a hydraulic external rotor pump, has a first component which is configured as an outer rotor with a sliding surface which is arranged on the outer side thereof, and a second component which is configured as an opposing body and in which the outer rotor is mounted rotatably by way of the sliding surface thereof on an inner guide surface of the opposing body and is in mechanical contact with the inner guide surface. An inner rotor which is mounted such that it can be rotated eccentrically with respect to the outer rotor is provided. One of the rotors can be driven, in order to be set into a rotational movement, and the rotors are coupled to one another such that, when the drivable rotor is driven, the other rotor is likewise set into a rotational movement as a result, in order to convey fluid from a suction region to a pressure region of the external rotor pump. The sliding surface or the guide surface has a surface structure which has a load-bearing region and a non-load-bearing region which is depressed in contrast with the former. The result is that the non-load-bearing region is saved from contact between the guide surface and the sliding surface which is mounted thereon.

A scroll compressor includes a fixed scroll, an orbiting scroll, a rotating shaft, an Oldham ring, and a plurality of first keys. The orbiting scroll is configured to engage the fixed scroll. The rotating shaft is eccentrically coupled to the orbiting scroll and configured to operate the orbiting scroll. The Oldham ring has a ring body that defines a plurality of slots. The plurality of first keys are coupled to the orbiting scroll and inserted to the plurality of slots, respectively. The plurality of first keys are configured to slide at the plurality of slots in a radial direction and include a material different from a material of the Oldham ring.

A cooling and lubricating arrangement of tribological contact areas is disclosed. The arrangement includes tribological contact areas that slide over one another, of which at least one contact area has a surface contour with surface depressions in which a lubricant is stored. The surface contour forms a number of elongate grooves, the gap heights of which, at least in respect of respectively two adjacent grooves, are preferably different.

The invention relates to a two-spindle screw pump of single-flow construction, comprising a pump housing, which has a pump portion, a bearing portion and a gear portion with a gear chamber, wherein the bearing portion and the pump portion are realized separately from each other characterized in that the gearwheel and the fastening element (and thus the shaft) are mutually rotatable, so that a spacing of the flanks of the feed screws (the flank clearance of the feed screws) is adjustable, that an opening is provided on the gear portion of the pump housing, that the opening is provided with a detachable cover, that the opening is arranged such that the cover is detachable in the mounted state of the screw pump, and that the gear chamber, for the adjustment of the flank clearance of the feed screws, can be reached with the tool necessary for this purpose.

An integrated pressure plate and port plate, and method of forming same, for a pump includes a housing having a pumping chamber formed therein. The housing includes first and second metal pressure plate portions that form at least a portion of the pumping chamber wherein at least one of the first and second pressure plate portions has a hard coating formed of a different material than a remainder of the housing metal on a surface thereof where integrated ports are formed on surface(s) of the pressure plate portion(s). Surface irregularities relieve stresses and promote adhesion of the coating (e.g., tungsten carbide) to the underlying metal (aluminum alloy).

Anti-wear surface coatings and methods for making them are provided. Such anti-wear surface coatings are particularly suitable for use in a compressor, such as a scroll compressor. A precursor powder material can be applied via spraying to a wear surface of a metal component of the scroll compressor. The precursor powder material comprises a powderized thermoplastic polymer (e.g., PEEK), a first lubricant particle (e.g., molybdenum disulfide (MoS.sub.2)) and a second lubricant particle (e.g., polytetrafluoroethylene (PTFE)). Then the applied precursor powder material is heated to form a substantially uniform coating covering the underlying metal component. The substantially uniform coating may have a thickness of less than or equal to about 0.005 inches (about 127 m).

The purpose of the present invention is to suppress the occurrence of unevenness in a rotor of an internal gear pump, suppress the formation of gaps between the end surfaces (side surfaces) of an inner rotor and an outer rotor, and to prevent a decline in volume efficiency. Thus, the pump device of the present invention includes an internal gear pump (10), in which an inner rotor (13) is inscribed to an outer rotor (12), and includes a plate member (7) which is provided to an end surface of the rotors. The plate member (7) is formed of a material having high hardness, has a shape that does not block a suction port (150), has a through-hole (73) formed therein, and has O-ring grooves (71,72), which each have a continuous shape and house an O-ring formed therein.

A scroll compressor is provided that may include a casing having a sealed inner space; a drive motor provided in the inner space of the casing to generate a rotational force; a rotational shaft rotatably coupled to the drive motor; an orbiting scroll formed of an aluminum material, and coupled to the rotational shaft to perform an orbiting movement; a fixed scroll coupled to the orbiting scroll to form a compression space; and an Oldham ring coupled to the orbiting scroll, and formed of a sintered metal. With this structure, it may be possible to prevent the Oldham ring from being worn out due to contact with the orbiting scroll. Further, a weight loss portion or wear-resistant coating layer may be formed on a portion of the Oldham ring, thereby suppressing or preventing vibration noise of the scroll compressor from being increased due to a weight increase of the Oldham ring.

A rotary compressor is disclosed. The rotary compressor may include a casing, a cylinder, main and sub bearings, a rotational shaft, a roller, at least one vane, and a vane support portion that axially supports the at least one vane formed on a bearing surface to extend along a reciprocating direction of the at least one vane from an inner circumferential surface of at least one back pressure pocket at an end of circumferential ends of the at least one back pressure pocket, adjacent to a contact point, and/or protrude axially from the inner circumferential surface of the at least one back pressure pocket and extend in a circumferential direction. This may secure a wide axial support area for a rear end of the at least one vane passing the contact point and/or near the contact point, to suppress or prevent axial tilting of the at least one vane, thereby reducing friction loss, wear, and vibration noise due to the axial tilting of the at least one vane during operation of the compressor.

A pump for conveying a fluid includes a casing with a casing inner wall, a pump interior, an inlet opening, an outlet opening, a displacement assembly, and a radial protective element arranged in the pump interior in order to line at least one radial section of the pump interior, the radial protective element bearing against a radial section of the casing inner wall. A fastening element is provided which can be arranged in a fastening position in which the fastening element bears against an edge of the radial protective element and in the process fastens the radial protective element in the pump interior, wherein the fastening element has a longitudinal extent which extends from a first axial end of the pump interior along a recess arranged in the casing inner wall.