An external rotor pump has an outer rotor with a sliding surface which is arranged on the outer side thereof, and an opposing body 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. The sliding surface or the inner 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.

A rotor can comprise a body having arcuate voids each presenting away from a rotation axis and, for each void, a vane. The vane is mounted to the body for pivotal movement between retracted and extended positions; is adapted to sweep the void in the manner in which a piston sweeps a cylinder during movement between the positions; and terminates in a tip. A stator defines the rotation axis; and has an annular surface which, in use, is swept by the tips during rotation of the body. The surface is positioned such that, in each rotation, each vane cycles between its extended and retracted positions. A sealing arrangement defines a pair of ports and, in combination with the rotor and stator, defines, in use, chambers that increase in volume when in communication with one of the ports and that decrease in volume when in communication with the other of the ports.

A rotary compressor includes a sealed longitudinal compressor housing which is provided with a discharge portion of a refrigerant at an upper portion thereof, is provided with an inlet portion of a refrigerant at a lower portion thereof, and in which lubricant oil is stored; a compressing unit which is disposed in the compressor housing, compresses a refrigerant sucked from the inlet portion and discharges the refrigerant from the discharge portion; a motor which is disposed in the compressor housing and drives the compressing unit via a rotation shaft; and an accumulator which is attached to a side portion of the compressor housing and is connected to the inlet portion of the refrigerant. When an inner diameter of a cylinder constituting the compressing unit is referred to as Dc, a height of the cylinder is referred to as Hc, and an eccentric amount of an eccentric portion of the rotation shaft is referred to as e, Dc, Hc, and e are set so that a value obtained by an expression (e+Hc).Math.(Dce).sup.1/3/(e.Math.Hc).sup.2/3 is less than 4.1.

A vane pump includes a housing, a rotor rotatable about a rotation axis, and a vane that rotates together with the rotor and reciprocates in a radial direction with respect to the rotor, the vane dividing a pump chamber into a plurality of working chambers. At least one of opposite end surfaces of the vane in an axial direction is a sliding surface that slidably contacts an inner surface of the housing via an oil film, and an oil reservoir portion is provided in the sliding surface in a recessed manner.

Various designs for hydraulic devices are disclosed including hydraulic devices that can include a rotor, vanes and a ring. The rotor can be disposed for rotation about an axis. The plurality of vanes can each include a vane step. 5 Each of the plurality of vanes can be moveable relative to the rotor between a retracted position and an extended position where the plurality of vanes work a hydraulic fluid introduced adjacent the rotor. A roller can be mounted to a tip of each of the plurality of vanes. The ring can be disposed at least partially around the rotor. The rotor can include one or more passages for ingress or egress of a 10 hydraulic fluid to or from a region adjacent the vane step and defined by at least the rotor and the vane step.

The present invention provides an improved vacuum pump assembly for a motor vehicle comprising of a housing, a rotor, modified vane, a sealing ring, a cover, wherein, the modified vane containing a vane slider is having at least one oil vent or relief hole or slot, for the reduction of the exit port oil peak pressure, by channelizing oil supplies to the vane top and bottom face, thereby improving the seal-ability between the moving and stationary part of the pump; and the modified vane further having an oil vent control at the exit port, for maintaining oil pressure and reducing the exit port hydraulic pressure, leading to reduction in the opposite end vane slider tip load causing low friction between the pump housing, the vane and vane slider, and further channelizing the excess amount of oil to the vane top face which creates additional sealing between the vane and the housing, reducing the air leakage between the low pressure chamber and high pressure chamber inside the pump.

A rotary compressor has a blade which is provided in a cylinder so that reciprocating movement can be performed. The blade partitions a cylinder chamber into a suction chamber and a compression chamber by making a tip end portion of the blade contact the outer peripheral surface of a roller. The blade includes two blade members provided so as to be superimposed in an axial direction of a rotary shaft. Tip end portions of the two blade members are made to contact the outer peripheral surface of the roller. The two blade members are energized by a coil spring so that superimposed portions of the blade members are made in contact.

This invention relates to the field of internal combustion engines and compressors in general and to linear compressors, in particular these used as in U.S. Pat. No. 8,056,527, by accurately controlling the pressure being delivered into the combustion chambers of said engine while returning unused energy of the compression phase into the motor for complete expansion. Another improvement relates to a pressure compensated vane to be used inside grooves of the motor assembly rotor. This invention enables the vane to seal against the cavity of the housing tightly with minimal force.

An improvement to an expander is disclosed. The expander is of the type that has vanes that extend and retract from a rotor body during rotation and create chambers that increase and decrease in size. The improvement comprises, for each vane, for each vane, a pivot axis orientated parallel to the rotational axis and about which said each vane pivots between the extended and retracted positions.

A pump includes a shaft to rotate about a longitudinal axis, a rotor, at least two arcuate slots extending continuously into and through the rotor, wherein each of the slots is curved along a longitudinal slot axis, and at least two arcuate vanes, each of the vanes being shaped to be slidably seated in one of the slots, each of the vanes being movable in the corresponding slot between an extended position with the external edge of the vane adjacent the interior sidewall of the housing, and a retracted position wherein the external edge of the vane does not extend beyond the cylindrical surface of the rotor. Each of the vanes is spaced from an adjacent vane about the rotor such that there is always at least one vane positioned between the fluid inlet and fluid outlet ports.