A gas pump including a delivery chamber with an inlet and an outlet for a gas. The delivery chamber is at least partially enclosed by a first housing part with a first sealing surface and a second housing part with a second sealing surface. A delivery device is moveable within the delivery chamber for delivering the gas. A pressing device presses one of the housing parts against the other with a pressing force such that the sealing surfaces abut each other and together form a sealing join which at least partially surrounds the delivery chamber in order to seal off the delivery chamber. The second housing part can be moved relative to the first housing part, against the pressing force, in order to be able to widen the sealing join to form a relieving gap through which liquid situated in the delivery chamber can escape.

A crankshaft assembly, a compressor and a refrigeration device are provided. The crankshaft assembly has an eccentric shaft component, a spindle component and a main screw oil pump. The eccentric shaft component has an eccentric cavity, and the spindle component has a first cavity communicated with the eccentric cavity. A first through-hole and a second through-hole in a first spindle are each communicated with the first cavity. An outer surface of the first spindle is provided with a first spiral oil groove connecting the first through-hole and the second through-hole. An outer surface of the main screw oil pump is provided with a second spiral oil groove along its length direction, and a spiral direction of the second spiral oil groove is opposite that of the first spiral oil groove.

An internal gear pump for forward and reverse operations, including: a pump housing which includes a first fluid port and a second fluid port, wherein in a first rotational direction, the first fluid port is formed as a fluid outlet and the second fluid port is formed as a fluid inlet, and in a second rotational direction, the first fluid port is formed as a fluid inlet and the second fluid port is formed as a fluid outlet; an internal gear and an external gear which together form delivery cells in order to deliver a fluid; a first rotary bearing which mounts the internal gear; and a second rotary bearing which mounts the external gear; and includes a lubricant feed which sets a fluid flow between the fluid ports through the two rotary bearings in both rotational directions.

A method of priming a pump includes supplying lubricant, via a priming flow path, into an interface defined between a first part of a shaft of the pump and a second part of the shaft coaxially engaged with the first part of the shaft to define the pump, the first part of the shaft rotatable about a rotation axis relative to the second part of the shaft, and supplying lubricant into the interface via a lubrication flow path that is different from the priming flow path. A method of lubricating an aircraft motor of an aircraft engine, and a machine for an aircraft engine are also described.

A rotary compressor is provided that may include a roller slidingly coupled to an eccentric portion of a rotational shaft so as to be moved along an inner circumferential surface of a cylinder by the rotational shaft, and a vane slidingly coupled to the cylinder so as to divide the compression space into a plurality of compression chambers. An oil supply groove may be formed on an outer circumferential surface of the eccentric portion or an inner circumferential surface of the roller that faces the outer circumferential surface of the eccentric portion, and a depth of the oil supply groove may decrease as a distance in a circumferential direction from the second oil supply hole increases. Accordingly, an amount of oil supplied between the eccentric portion and the roller may be increased to thereby reduce friction loss.

An inner gear includes: sliding surface parts that are provided annularly at an outer peripheral part including a plurality of outer teeth on both sides of the inner gear in its axial direction and that slide on a pump housing; recessed parts that are respectively provided radially inward of the sliding surface parts to respectively form fuel chambers, into which fuel flows, between the recessed parts and the pump housing; and a communication hole that communicates between the recessed parts. The inner gear further includes an inclined surface part that is provided at an edge portion of a communicating edge portion on a rotation advance side of the inner gear, to avoid an adjacent part adjacent to an inner peripheral edge portion of each of the sliding surface parts and that is inclined further toward a rear side in a direction to a central part of the communication hole.

A liquid pump of the present disclosure includes a container, a shaft, a bearing, a pump mechanism, a storage space, and a liquid supply passage. The shaft is disposed in the container. The bearing supports the shaft. The pump mechanism pumps a liquid by rotation of the shaft. The storage space is defined in the container at a position outside the pump mechanism. The storage space stores the liquid to be taken into the pump mechanism or the liquid to be discharged to outside of the container after being expelled from the pump mechanism. The liquid supply passage is a flow path including an inlet open to the storage space and supplying the liquid stored in the storage space to the bearing.

A gear bearing structure for an external gear pump includes a driving gear and the driven gear accommodated rotatably in a pump body of the external gear pump, an inlet chamber formed on one side of a mesh portion of the driving gear and the driven gear, an outlet chamber formed on the other side of the mesh portion, a hollow cylindrical bushing for holding a rotational shaft of the driving gear or the driven gear with a lubricating liquid film formed between itself and the rotational shaft, and a ring plate spring disposed between the pump body and the bushing to urge the bushing so as to slidably contact with a side face of the one of the driving gear and the driven gear.

A rotor has at its two axis end portions an upper large-diameter inner circumferential portion and a lower large-diameter inner circumferential portion that have inner diameters larger than the inner diameter of the axially middle portion of the rotor and are offset in the radial direction. A crankshaft has a passageway, which is formed in the crankshaft and allows refrigerant to flow therethrough, and a gas venting hole, which provides communication between the passageway and at least one discharge opening formed in the outer circumferential surface of the crankshaft. The at least one discharge opening is formed at a position facing the inner circumferential surface of the lower large-diameter inner circumferential portion 5b on the compression unit side.

A gerotor pump includes a rotor wherein only on the face wall of the rotor that lies adjacent to a pressure kidney and a suction kidney, a lubrication surface inclined in the direction of rotation of the rotor, relative to the surface plane of the face wall of the rotor, is disposed on each tooth, in each instance, over its tooth height, either starting directly in the center tooth plane or starting “offset” ahead of the center tooth plane in the direction of rotation of the rotor, which surface is formed from a level surface or multiple, always level partial surfaces that follow one another, which enclose an angle of inclination relative to the surface plane of the face wall of the rotor, in each instance, which angle lies in the range from 0.2° to 7°, in each instance.