A mechanical lubricant pump includes a control ring which shifts between a maximum and a minimum eccentricity position, the control ring having a circumference with anti-spring and pro-spring hydraulic surfaces, a pump rotor having slidable vanes which rotate in the control ring, a preload spring which pushes the control ring into the maximum eccentricity position, a hydraulic pilot chamber which pushes the control ring into the minimum eccentricity position, a hydraulic pressure control circuit which controls a gallery pressure by regulating a pilot chamber pressure, and a hydraulic outlet chamber which surrounds a part of the circumference. The hydraulic pilot chamber is charged with a pump outlet pressure or with the gallery pressure of an engine. The hydraulic outlet chamber is charged with the pump outlet pressure and is connected to the pump outlet for a pressurized lubricant. The anti-spring hydraulic surface is larger than the counter-acting pro-spring hydraulic surface.

Various designs for hydraulic devices are disclosed including hydraulic devices that can include a rotor and a ring are disclosed. The rotor can be disposed for rotation about an axis and can have a plurality of plurality of vanes extending therefrom. The ring can be disposed at least partially around the rotor and the ring, and the rotor can be in communication with a port for ingress or egress of the hydraulic fluid to or from adjacent the rotor. The ring defines a cavity adjacent to and in communication with the port, the cavity allows the hydraulic fluid to be disposed adjacent at least one of the plurality of vanes when the at least one of the plurality of vanes is transiting the port.

A rotary pump includes: a housing featuring a housing inlet and a low-pressure space on a low-pressure side of the pump and featuring a housing outlet and a high-pressure space on a high-pressure side of the pump; a delivery chamber; a delivery rotor in the delivery chamber; a setting structure which can be moved in a first setting direction and, counter to the first setting direction, in a second setting direction in order to perform a setting movement which adjusts the specific delivery volume of the rotary pump; and at least a first setting chamber for charging the setting structure with a setting pressure which acts in the second setting direction, wherein the fluid pressure in the high-pressure space acts on a pressure equalization surface on the outer circumference of the setting structure resulting in an external additional force which acts on the setting structure in the first setting direction.

A rotary pump, preferably a vane cell pump or a pendulum slider pump, includes a stator and a rotor which rotates about a rotational axis within the stator. The rotor includes multiple delivery elements which move radially in relation to the rotational axis, and two adjacent delivery elements limit a delivery cell together with the outer surface area of the rotor and the inner surface area of the stator. At least two delivery cells, preferably two adjacent delivery cells, exhibiting a first maximum cell volume form a first delivery cell group and at least two other delivery cells, preferably two other adjacent delivery cells, exhibiting a second maximum cell volume form a second delivery cell group. The first maximum cell volume of the delivery cells of the first delivery cell group is larger than the second maximum cell volume of the delivery cells of the second delivery cell group.

A rotary positive displacement pump (1) comprises a pump enclosure (10) and at least one rotating member (20). The pump enclosure (10) has an inlet (12) and an outlet (14). The rotating member (20) is arranged for, when being rotated, causing a transfer of a liquid from the inlet (12) to the outlet (14). The rotary positive displacement pump (1) has internal sliding surfaces (16, 24, 26, 32, 34) that during operation are exposed to the liquid and are exposed to a sliding contact relative to other internal sliding surfaces (16, 24, 26, 32, 34) of the rotary positive displacement pump (1). At least a part of the internal sliding surfaces (16, 24, 26, 32, 34) has a surface region composed by a nitrided or nitrocarburized steel intercalated with a solid lubricant. A method for manufacturing a rotary positive displacement pump is also disclosed.

A gear configured to rotate as a unit with a shaft, the gear includes: a plurality of annular grooves formed on both side surfaces of the gear in a direction of a rotation axis of the shaft, at least partially overlapped when viewed from the direction of the rotation axis, and at least partially overlapped in a radial direction with respect to the rotation axis.

A gas delivery augmenter may include a pump mechanism for facilitating inflation of an inflatable. The pump mechanism is generally configured to be driven/powered by pressure-volume energy from a primary gas received by the gas delivery augmenter, and the pump mechanism of the gas delivery augmenter is configured to entrain a secondary gas deliver the entrained secondary gas (and any remaining primary gas) to the inflatable. The pump mechanism, as described in greater detail below, enables secondary gas to be pumped/delivered to the inflatable even as the inflatable backpressure increases, thus providing improved inflation over conventional aspirators.

A composite piston machine has two moving assemblies of a rotor and a composite piston placed 180° out of phase with each other and linked to a shaft eccentrically placed inside the inner cavity of a main body that has ports for the inlet and outlet of fluids from it. This inner cavity is covered by two lids and divided in two working chambers by a separator. The composite pistons move following the rotation of the rotors while oscillating with respect of them and following the path of skid guides carved in separator and lids, dividing each working chamber in inlet and outlet chambers of variable volume, and intermittently obstructing the inlet and outlet of fluids from the inner cavity through the ports. The machine is designed for compressing gases or pumping liquids and can also operate as an engine driven by compressed gases or with pressurized liquids.

The present disclosure provides an oil pump including a housing in which a space is formed, a rotor installed to be rotatable in an eccentric position in the housing and having vanes mounted along a circumference direction to be protruded and retracted in a radial direction of the housing, and an inner ring fitted to an inner surface of the housing and rotated along with the rotor when the rotor rotates. The housing is formed of a material harder than the material of the inner ring, and oil for lubrication is provided between the housing and the inner ring.

The invention relates to a vane pump for conveying liquids, in particular viscous oils, which vane pump comprises: a rotor having sliding slots in which movable vanes are held and can be countersunk in relation to a rotor radius (r); a pump housing comprising a pump chamber, which encloses the rotor; and an inlet and an outlet, which open into the pump chamber at at least one end face of the rotor; radial elevations protruding, with respect to the sliding slots, over the circumference of the rotor, which elevations form a rotor radius (r) on either side of the vanes that can be countersunk, and radial pockets being recessed, relative to the rotor radius (r), between the radial elevations. Within the radial elevations, recesses are formed on the at least one end face of the rotor at which the inlet and the outlet open, which recesses provide rotating anticipatory control geometry for reducing pressure spikes in the vane cells.