A compressor comprises a housing including a first opening to form a receiving space and a retaining wall, wherein the receiving space is divided, by the retaining wall, a low-pressure chamber and a controller chamber. A compressing mechanism further comprises a fixed scroll plate including a low-pressure side of scroll wraps and a high-pressure side, opposite to the scroll wraps; an orbiting scroll plate, located in the receiving space, including a side, facing the scroll wraps of the fixed scroll plate, of scroll wraps and a compression chamber is formed by the scroll wraps of the fixed scroll plate and the scroll wraps of the orbiting scroll plate; an electrical machinery mechanism, located in the low-pressure chamber, including a rotor and a stator, wherein the electrical machinery mechanism drives the compressing mechanism to rotates to compress refrigerant in the compression chamber.

A light weight vacuum pump is made with either or all of the stator, rotors and vanes made of aluminum or aluminum alloy that has been subjected to high energy oxidation, such as plasma electrolytic oxidation (PEO), electrolytic plasma oxidation (EPO) or micro-arc oxidation (MAO), to treat and harden the surface.

The invention relates to a rotary vane vacuum pump comprising a housing member whose inner wall defines at least one pumping space, and a rotor that is arranged for rotation in the pumping space and has a rotor member and at least one vane, wherein the vane projects radially beyond the rotor member and together with the inner wall of the housing body a pumping volume that can be pumped by rotation of the rotor from an inlet to an outlet of the rotary vane vacuum pump, wherein the vane, at least in a region cooperating with the inner wall, comprises a polytetrafluoroethylene material containing polyimide particles and manufactured by hot pressing and sintering, and wherein the inner wall has a slide layer at least in a region cooperating with the vane, said slide layer comprising an oxide layer formed by anodic oxidation in an electrolyte including oxalic acid.

A method for producing a housing for a rotary piston engine, a shell housing, and a housing for a rotary piston engine, are disclosed. A bushing of hard metal is pressed into a shell housing main body with a trochoidal raceway in such a manner that an external circumferential contour of the bushing bears in a sealing manner on the trochoidal raceway and the trochoidal raceway is cladded via the bushing.

A vacuum pump rotor comprises at least one displacement element arranged on a rotor shaft. The rotor shaft comprises at least one shaft end for a bearing element to be arranged thereon. The rotor element, the at least one displacement element and the at least one shaft end are made from aluminum or an aluminum alloy.

The pump device includes a housing defining insertion holes for a rotation shaft, inlets and outlets, and an internal passage; a first pump element; and a second pump element. The internal passage includes first suction passages communicating from the inlet to a first suction port facing the first end surface of the first pump element directed to one end side; first discharge passages communicating from a first discharge port facing the first end surface to the outlet; second suction passages passing around the first pump element to communicate from the inlet to a second suction port facing the second end surface of the second pump element; and second discharge passages passing around the first pump element to communicate from a second discharge port facing the second end surface to the outlet.

A vacuum pump screw rotor, comprising at least two helical displacer elements on a rotor shaft. The at least two displacer elements have different pitches, but the pitches of each displacer element are constant. Furthermore, the displacer elements each have a helical recess, each having a contour that remains the same over its entire length. Hereby, a suction-side displacer element has a recess having an asymmetric contour, and a pressure-side displacer element has a recess having a symmetrical contour.

A screw vacuum pump comprises a housing forming a pumping chamber, wherein the housing is made of aluminum or an aluminum alloy. Further provided are two screw rotors arranged in the pumping chamber, each screw rotor comprising at least one displacer element having a helical recess for forming a plurality of windings, wherein the at least one displacer element is made of aluminum or an aluminum alloy. Between the region in which prevail 5% to 30% of the outlet pressure and a pressure-side end of the rotor (pump outlet), at least six, particularly at least eight, and with particular preference at least ten windings are provided.

A journal bearing for a gear driven pump includes a bearing body having a bearing body circular opening that defines a bearing surface along a length of the bearing body and a face plate adjacent to the bearing surface. The bearing surface is configured to carry a gear shaft load through a hydrodynamic fluid film pressure between a load surface of a gear shaft and the bearing surface. The bearing surface is formed from a leaded bronze material and the face plate is formed from a copper-nickel alloy.

A cover assembly for on-board electric equipment includes a cover body and a connector including a terminal and a connector housing. The cover body includes a ferrous base metal body, and a Zn-based plating layer formed on a surface of the base metal body. The cover body has a through hole formed through the base metal body and the plating layer. The terminal is passed through the through hole and electrically connected to an electric circuit. The connector housing is formed on the cover body so as to surround the terminal. A laser mark is formed on the cover body. The laser mark has a circular shape about the through hole and penetrates the plating layer to the base metal body. The connector housing extends to the base metal body through the plating layer within the laser mark.