A method of treating, tuning, assembling, and/or overhauling a twin rotor device (200, 1200) includes applying a coating material (102) on an internal set of working surfaces (218, 222, 224, 226, 228, 1218, 1222, 1224, 1226, 1228) of the twin rotor device when at least partially assembled. The coating may be factory or field applied to a new or used twin rotor device. The working surfaces may be uncoated or previously coated and may be built-up as the coating material forms a coating (206, 1206) on at least some of the working surfaces. Manufacturing variations of a pair of rotors (220, 1220) and a housing (210, 1210) may be compensated by the coating. One or more performance characteristics of the twin rotor device may be improved by the coating, and variation between a series of twin rotor device may be reduced or substantially eliminated. The coating may reduce internal leakage and increase volumetric efficiency of the twin rotor device. The twin rotor device may be a supercharger 200, a screw compressor 1200, or other twin rotor device.

An oil pump, in particular an electric or electromotive auxiliary pump for a motor vehicle, having a housing having an inlet on the admission side and an outlet on the pressure side, in addition to a pump rotor which is inserted in the housing such that it can rotate about an axis, and having at least one rotor part, a flexible housing component which is in the form of an elastic press plate and which extends over the cross-sectional surface of the pump rotor. The flexible pressure plate is maintained, in an advantageous manner, in the edge area of the second housing parts.

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.

An upper piston of a rotary compressor is formed to satisfy 0.7Hcy1/1000ro1.2Hcy1/1000, Cro10.1, Cro20.1, and Cro1Cro20.007. Here, Cro1 indicates a length (mm) of an upper side piston outer circumferential chamfer portion in a height direction, and Cro2 indicates a length (mm) of the upper side piston outer circumferential chamfer portion in a normal line direction of a piston outer circumferential surface. An upper vane is formed to satisfy 0.7Hcy1/1000v1.2Hcy1/1000, Cv10.06, Cv20.06, and Cv1Cv20.003. Here, Cv1 indicates a length (mm) of an upper side vane ridge line chamfer portion in a height direction, and Cv2 indicates a length (mm) of the upper side vane ridge line chamfer portion in a normal line direction of a vane tip end surface.

The present disclosure provides a compressor and an air conditioner. The compressor includes a housing; a first rotating shaft mounted in the housing; a connecting assembly sleeved on the first rotating shaft; and a first rotor assembly including a first rotor and a second rotor coaxially disposed on the connecting assembly. The connecting assembly carries the first rotor and the second rotor to rotate about the first rotating shaft together. The connecting assembly is configured to limit the relative positions of the first rotor and the second rotor, such that there exists a clearance between the first rotor and the second rotor. The present disclosure can maintain a clearance between the first rotor and the second rotor without increasing the number of components of the compressor.

A crescent internal gear pump includes a front cover, an end cover, a ring gear and a pinion gear disposed within a gear housing in an eccentric, intermeshing relationship. The housing is disposed intermediate the front cover and the end cover. A crescent is disposed radially intermediate the ring gear and the pinion gear. The crescent partially extends into a correspondingly shaped slot in the end cover. The gear housing, the ring gear, and the pinion gear can have substantially the same thickness. A shim can be disposed intermediate the end cover and the gear housing for establishing a desired clearance therebetween.

A screw compressor for compressing a working medium sucked through a suction opening and discharging the compressed working medium through a delivery opening, wherein the screw compressor includes: a male rotor and a female rotor that rotate while meshing with each other; a casing that houses the male rotor and the female rotor and is provided with a bore which forms a working chamber designed, together with the male rotor and the female rotor, to compress the working medium; a drive unit that rotationally drives at least one of the male rotor and the female rotor; a working chamber closing unit that forms a suction port for sucking the working medium into the working chamber and closes the working chamber when the working chamber reaches a specified capacity; and a suction space that connects the suction opening and the suction port to allow communication therebetween, wherein an open space that connects the suction opening and the suction port to allow communication therebetween is provided between a shaft of the male rotor and a shaft of the female rotor on an opposite side of the male rotor and the female rotor relative to the suction port.

An improved screw pump such as, for example, a twin screw pump, includes a casing including an internal chamber, and first and second rotors rotatably positioned within the chamber of the casing. The first and second rotors have an intermeshing threaded-shape profiling. A plurality of bearing seal assemblies are provided at each end of the first and second rotors. Each bearing seal assembly includes a bearing positioned about an end portion of a rotor to facilitate rotation of the rotor, and a seal positioned about an end portion of a rotor to seal passage of the rotor through the casing. The bearing is coupled to the seal so that the seal may be secured to the casing via the coupling of the bearing to the casing.

A pump includes a first housing part defining a first portion of a bore extending within the first housing part and shaped to receive a rotor; and a second housing part defining a second portion of the bore extending within the second housing part and shaped to receive the rotor. The first housing part has a first face abutable against an opposing second face of the second housing part to position the first portion of the bore with the second portion of the bore to receive the rotor. The first portion of the bore has a first circular cross-section portion centered along the first face and the second portion of the bore having a second circular cross-section portion centered, within the second housing part, at a distance from the second face.

A scroll compressor includes a fixed scroll and a movable scroll. The fixed scroll has a spiral fixed-side wrap positioned upright on a surface of a fixed-side plate. The movable scroll is orbitably disposed to face the fixed scroll. The movable scroll has a spiral movable-side wrap positioned upright on a surface of a movable-side plate, with the movable-side wrap being configured to mesh with the fixed-side wrap. A side clearance is formed between a side surface of the fixed-side wrap and a side surface of the movable-side wrap so as to increase from an outer peripheral side toward an inner peripheral side of each of the wraps.