A motor pump unit comprises an electric motor and a reversible internal gear machine. The latter has a multi-part housing in which an externally toothed pinion and an internally toothed hollow gear are arranged. A free space, in which a multi-part filler element is arranged, is configured between the gears. The filler element comprises radially movable sealing segments, between which a radial gap is configured. An axially movable sealing plate is arranged between axial faces of the gears and a housing part. This has a sealing plate control groove that is open to the faces of the gears and that can be pressurized, and which is open to the radial gap and located directly opposite thereto. The pinion segment and/or hollow gear segment has a radial sealing segment control channel that can be pressurized and extends transversely, is open to the radial gap, and ends directly in the radial gap.

The present disclosure provides a forklift, an internal gear pump, and an axial compensation component thereof. The axial compensation component for the internal gear pump is configured to be sandwiched between a pump cover of the internal gear pump and a gear pair of the internal gear pump, and the axial compensation component includes: a floating side plate; and a floating sleeve fixed at a side of the floating side plate far away from the gear pair, in which a part of the floating sleeve is configured to extend into an oil storage tank of the pump cover, the oil storage tank is configured to be in communication with a high-pressure oil area of the internal gear pump, and the floating side plate is configured to press tightly against the gear pair under an oil pressure in the oil storage tank.

A crescent internal gear pump includes a front cover, an end cover, a ring gear and a pinion gear disposed within a gear housing in an eccentric, intermeshing relationship. The housing is disposed intermediate the front cover and the end cover. A crescent is disposed radially intermediate the ring gear and the pinion gear. The crescent partially extends into a correspondingly shaped slot in the end cover. The gear housing, the ring gear, and the pinion gear can have substantially the same thickness. A shim can be disposed intermediate the end cover and the gear housing for establishing a desired clearance therebetween.

A hypotrochoid positive-displacement machine includes an inner rotor and an outer rotor with intermeshing projections. During rotation of the rotors, the inward-most tips of the outer rotor trace hypotrochoid paths relative to the inner rotor. A driven rotor, for example the inner rotor, drives a driven rotor, for example the outer rotor, by contact between driving surfaces and driven surfaces of the respective rotors. Improvements are provided, for example in relation to the contact between the rotors. In use of the device contact between the driving surfaces and driven surfaces may move radially outward from a point of initial contact. The driving or driven surfaces or both may be arranged to flex under contact between the rotors. The driving surfaces may be convex. The driven surfaces may be concave.

An internal gear fluid machine includes a first gearwheel having an external toothing and mounted rotatably about a first axis of rotation, and a second gearwheel having an internal toothing meshing in regions with the external toothing in an engagement region and mounted rotatably about a second axis of rotation different from the first axis of rotation. The internal gear fluid machine additionally includes a filler piece arranged between the first gearwheel and the second gearwheel away from the engagement region, which filler piece bears on one side against the external toothing and on the other side against the internal toothing, in order to divide a fluid space present between the first gearwheel and the second gearwheel into a first fluid chamber and a second fluid chamber. Sealing discs are arranged in the axial direction with respect to the first axis of rotation on both sides of the first gearwheel and the second gearwheel, which, during operation of the internal gear fluid machine, bear in a sealing manner against the first gearwheel and the second gearwheel, and an axial opening is formed in each of the sealing discs. A common one of the fluid chambers is in flow communication with the same fluid connection of the internal gear fluid machine via both axial openings.

A gear pump includes a pair of gears that meshes with each other, two rotational shafts inserted into the respective gears that rotate together with gears, a pair of side plates arranged adjacent to both side surfaces of the gears, each having two through-holes forming bearings of the two shafts, a seal block that abuts against the pair of side plates and covers a part of the pair of gears, a pump assembly having the gears, the two shafts, the pair of side plates, and the seal block, and a case having a recess to accommodate the pump assembly. A line passing through an arc center of a cylindrical surface inscribed in the facing surface of the case, and parallel to the two shafts, forms a rotating axis. When the pump assembly rotates about the rotating axis, one of the of side plates contacts the inner wall of the case.

The purpose of the present invention is to suppress the occurrence of unevenness in a rotor of an internal gear pump, suppress the formation of gaps between the end surfaces (side surfaces) of an inner rotor and an outer rotor, and to prevent a decline in volume efficiency. Thus, the pump device of the present invention includes an internal gear pump (10), in which an inner rotor (13) is inscribed to an outer rotor (12), and includes a plate member (7) which is provided to an end surface of the rotors. The plate member (7) is formed of a material having high hardness, has a shape that does not block a suction port (150), has a through-hole (73) formed therein, and has O-ring grooves (71,72), which each have a continuous shape and house an O-ring formed therein.

A rotary action, self-priming positive displacement constant flow high capacity fluid pump is described. None of the pump parts touch in the pump chamber to minimize pump wear allowing for extended pump life. Since there are no touching parts in the pump chamber, the pump can be operated dry without the pump liquid being present without damage to the pump. The pump may be operated either clockwise or counter-clockwise without loss of positive displacement or reduction in fluids input or output. Due to the design of the pump, the pump is inherently low-maintenance and is highly resistant to clogging by debris and the like. Fluid pressure relief sections are provided by carving out of the inside portions of the housing structure to which the ends of the shaft are mounted to vary or improved pump performance.

The invention relates to an internal gear machine (10) having a housing (12) which forms a cavity (14) in which an internally toothed ring gear (18) and an externally toothed pinion (16) are arranged, the toothings (24, 26) of which are in meshing engagement with one another in certain regions and the axes of rotation (20, 22) of which run parallel to and spaced apart from one another, wherein at least one filler piece (30, 30) rests against the first and second toothings (24, 26), which divides the cavity (14) into two fluidically separate regions. It is provided that the toothing (24, 26) is designed as helical toothing or arrow toothing.

Rotary positive displacement machines can include a rotor having a teardrop-shaped profile that undergoes planetary motion relative to a stator having an elliptical or near-elliptical profile. In some embodiments, these rotary positive displacement machines can be used for a variety of applications including as positive displacement pumps. In some embodiments the rotor and stator are helical. In some embodiments the rotor comprises a dynamic seal. Aspects of the machine geometry can be selected to provide operational and/or durability benefits.