In the present invention, polishing lines 71f are connected to an outer circumferential high-pressure region, but are not connected to each area that is a low-pressure region. In this configuration, the polishing lines 71f are connected to the outer circumferential high-pressure region where there is high discharge pressure, so high-pressure brake fluid is introduced within the polishing lines 71f. Therefore, a pushback effect is obtained, wherein gear pumps 19 and 39 are pushed back on the basis of the high-pressure brake fluid pressure. Furthermore, the polishing lines 71f are connected to the outer circumferential high-pressure region but are not connected to each area that is a low-pressure region, so high-pressure can be maintained within the polishing lines 71f, and a reduction in the pushback effect can be prevented. Accordingly, a decrease in the loss torque reduction effect can be prevented, and the loss torque can be further reduced.

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 invention provides a gear pump having one or more gears with bearing shafts supported by respective pressure-loaded gear pump bearing blocks. Each pressure-loaded bearing block has: a bore adapted to receive the bearing shaft of a gear of the pump; a thrust face at one end adapted to slidingly engage with a side surface of the gear, and an opposing rear face at the other end, the pump being adapted such that, in use, pressurised fluid is supplied to the rear face to provide a hydraulic load urging the thrust face of the bearing block towards the side surface of the gear; and a seal carried by the rear face, the seal, in use, partitioning higher fluid pressure and lower fluid pressure portions of the rear face. The gear pump further has a pressure regulating valve arranged such that, in use, the fluid pressure difference between the higher and lower fluid pressure portions of the rear face of the bearing block is adjustable by the valve to vary said hydraulic load.

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 pump for an engine includes a suction chamber, a discharge chamber, and a piston at least partly received within a relief chamber. The piston has first and second passageways provided therein. The second passageway is located closer to a face of the piston than the first passageway. The piston is movable within the relief chamber, so that the volume of the fluid transfer from the suction chamber to the discharge chamber is varied according to a pressure in the relief chamber. The first and second passageways form fluid paths between the suction chamber and the discharge chamber at a first and second pressure in the relief chamber, respectively, the first pressure being less than the second pressure.

A bearing structure for abutting a pair of gears of a gear pump includes a body including a face on which the gears rotate, an inlet defined in the body, and an outlet defined in the body. The bearing structure includes a sealing portion of the face configured to fluidly seal the inlet from the outlet, the sealing portion being defined as a portion of the face in sealing engagement with the gears at a rotational position of the gears wherein a volume contained by teeth of the gears and the face is constant or about constant as the gears rotate.

A geared fluid machine has a machine housing and first and second intermeshing gearwheels that are rotatably mounted in the machine housing with respect to an axis of rotation and are arranged at least partially contacting by their end faces. At least one axial washer is arranged in the machine housing with axial play and has on a distal side a pressure field surrounded by a circumferential seal. The seal contacts and seals against a first bearing surface of the axial washer, and also contacts and seals against a second bearing surface of the machine housing. The seal is at least partially U-shaped in section and has a first seal limb contacting the first bearing surface, a second seal limb contacting the second bearing surface, and a connecting limb connecting the first and second seal limbs.

The disclosure relates to an internal gear pump as a hydraulic pump for a slip-controlled vehicle brake system. The disclosure proposes to configure the internal gear pump as a preassembled module with a cartridge as housing, which can be pressed into a receptacle of a hydraulic block of the vehicle brake system. The cartridge has two steps which are parallel to one another for attaching a press-in ram and for orienting the cartridge in an angularly correct manner by means of the press-in ram, and a sealing surface, with which the cartridge bears in a sealed manner in the receptacle of the hydraulic block when the cartridge is pressed into the receptacle.

In a hollow seal member kept in abutted-engagement with a shaft hole formed in a housing via an elastic body and kept in sliding-contact with an outer circumference of a drive shaft for sealing against a leakage of fluid from a pump chamber, the seal member is provided with a seal part formed within an area at one end and kept in sliding-contact with the outer circumference of the drive shaft over a given hollow inner circumferential surface, and a rotation-stopping part formed within an area at the other end for restricting a movement of the seal member in a rotation direction of the drive shaft. A rotational resistance of the rotation-stopping part to the drive shaft is set to be less than a rotational resistance of the seal part.

A gear machine comprises a housing, at least two gearwheels positioned within the housing, and a bearing body defining a circular-cylindrical outer surface segment and a bearing bore. The at least two gearwheels configured to mesh in external engagement with each other. At least one of the gearwheels includes at least one bearing journal rotatably positioned within the bearing bore. The bearing body is positioned within the housing with the circular-cylindrical outer surface segment engaging a corresponding bearing surface defined on the inside of the housing. Each of the at least two gearwheels includes a plurality of tooth tips configured to engage a corresponding sealing surface defined on the inside of the housing. At least one segment of at least one of the sealing surface and the bearing bore is eccentric with respect to the circular-cylindrical outer surface segment of the bearing body. A method of production is also provided.