A gear pump is capable of maintaining the pump volumetric efficiency for preferably supplying a hydraulic liquid while adequately securing a sealing area, even if a cross sectional area of a flow-in passage is increased. The cross section of a suction passage has a rectangular shape in a side close to a hollow space in a body, and has a circular shape in the outside of the body. The rectangular shape of the suction passage in the hollow space side in the body has a long side extending in a direction along the tooth width of the spur gears, and a short side extending along a direction perpendicular to the tooth width direction. The suction passage has a shape that smoothly connects the rectangular shape in the hollow space side in the body with the circular shape in the outside of the body.

A screw pump, including a housing with a running bore having at least two intersecting bores, each of which receives a spindle, wherein the spindles have worm screw profiles which intermesh in portions and in operation bend in a defined bending direction under a hydraulic bending pressure, wherein each bore is configured as a slot with a longer first axis of symmetry and a shorter second axis of symmetry standing orthogonally thereto, wherein the longer first axis of symmetry runs in the bending direction.

A gear pump is capable of maintaining the pump volumetric efficiency for preferably supplying a hydraulic liquid while adequately securing a sealing area, even if a cross sectional area of a flow-in passage is increased. The cross section of a suction passage has a rectangular shape in a side close to a hollow space in a body, and has a circular shape in the outside of the body. The rectangular shape of the suction passage in the hollow space side in the body has a long side extending in a direction along the tooth width of the spur gears, and a short side extending along a direction perpendicular to the tooth width direction. The suction passage has a shape that smoothly connects the rectangular shape in the hollow space side in the body with the circular shape in the outside of the body.

An in-wheel motor vehicle drive device includes an electric motor driving a drive gear, and the drive gear provided with a gear portion configured to receive drive force of the drive gear and a first wall surface extending along a direction orthogonal to an extending direction of a rotation center axis of the gear portion, the first wall surface for forming a pump chamber. The in-wheel motor vehicle drive device further includes a hub configured to transmit the drive force to the wheel, and an oil pump driven by the electric motor. The oil pump includes an oil pump cover including a second wall surface facing the first wall surface of the pump chamber, and a pump rotator arranged at a space between the first wall surface of the driven gear and the second wall surface of the oil pump cover, the pump rotator integrally rotating with the driven gear.

A rotary pump, the rotational direction of which can preferably be switched, featuring: a housing including a pump space featuring an inlet into a low-pressure region of the pump space for a fluid to be pumped and an outlet from a high-pressure region of the pump space for the fluid to be pumped; at least one rotor which forms delivery cells in the pump space; a bearing; and a sealing stay which axially faces the at least one rotor and separates the low-pressure region from the high-pressure region in the rotational direction of the at least one rotor; and featuring at least one lubricant feed, in the sealing stay, which feeds a fluid, as a lubricant, from at least one of the delivery cells to the bearing.

An oil pump is configured to include a rotor, a drive shaft that drives the rotor to rotate, a rotor chamber in which the rotor is contained, an inlet port and an outlet port each provided in the vicinity of the rotor chamber, and a pump cover. The pump cover is made of a resin. On a portion of an outer surface side of the pump cover corresponding to an inner portion, in which oil circulates, of the pump cover, a rib that has an erecting wall shape is provided.

Lobe pumps have rings which can be located at least partially in at least one of cover plates and rotors, if not both to provide at least thrust bearings to space the rotors from the cover plates. Some rotors may have voids in ears to make the rotor lighter in weight with the voids potentially capped, symmetrically disposed, arcuately shaped and/or have other desirable features. Some rotors may have ears extending beyond cutouts which may extend beyond hubs, if not beyond hub extensions as well which may receive cover spigots thereabout. Some rings may act as radial bearings as well when located in the cover spigots.

A pump includes a casing defining an interior volume. The pump casing includes at least one balancing plate that can be part of a wall of the pump casing with each balancing plate including a protruding portion having two recesses. Each recess is configured to accept one end of a fluid driver. The balancing plate aligns the fluid displacement members with respect to each other such that the fluid displacement members can pump the fluid when rotated. The balancing plates can include cooling grooves connecting the respective recesses. The cooling grooves ensure that some of the liquid being transferred in the internal volume is directed to bearings disposed in the recesses as the fluid drivers rotate.

A momentum pump apparatus for mechanically pumping fluids includes a pump housing defining a housing inside. A housing front side has a fill aperture extending through to the housing inside. A housing back side has a supply aperture extending through to the housing inside. A fluid line is coupled within the pump housing and is in fluid communication with the supply aperture and the fill aperture. A pump is coupled within the pump and is in fluid communication with the fluid line to bring fluid from the supply aperture to the fill aperture. A gear system is coupled within the pump housing and includes a weighted disc to maintain momentum once spinning. The gear system is in operational communication with the pump. A handle assembly is coupled to the pump housing and is in operational communication with the gear system to operate the pump.

Provided is an internal gear pump in which a casing and a cover can be easily positioned to each other when the casing and the cover are assembled, and they can be prevented from separating or falling off. In an internal gear pump 1, at least one of a casing 5 and a cover 6 is a molded body of a resin composition and the like. The casing 5 and the cover 6 are fixed with a plurality of protrusion parts protruding from one of the casing 5 and the cover 6 fitted in the other. The protrusion parts protrude from the casing of metal bushes 9 fixed to the casing 5, and the casing 5 and the cover 6 are integrated by bolts 13 passing through the metal bushes 9 across these two members.