A gear pump comprises an internal gear (10), a first external gear (20) and a second external gear (30), a case member (50) having a one end side accommodation portion (52) for retaining these gears (10,20,30), an other end side accommodation portion (53) at other end side and a partition wall portion (54) therebetween, a cover member (70) and a plate member (80). A pump chamber (P) defined inside the internal gear (10) is divided into a first pump chamber (P1) which has a first intake-discharge space (L1) and a first discharge-intake space (H1), and a second pump chamber (P2) which has a second intake-discharge space (L2) and a second discharge-intake space (H2). The plate member has a first communication path (81) and a second communication path (82) between the plate member (80) and the cover member (70). The one side communication passage (57) is communicated with the first communication path (81). Two penetrating holes (82b,82c) are formed on the plate member (80). An other side communication passage (82a), which communicate the two penetrating holes (82b,82c) with each other, is formed between the plate member (80) and the cover member (70).

A pump particularly for pumping a liquid such as ink, paint, glue or the like, includes at least one rotating pumping member having a respective shaft. The at least one rotating pumping member being at least partially housed inside a pump body, the shaft being rotatably supported by at least one support associated with the pump body.

The shaft has on its external cylindrical surface in contact with the liquid one, or more recesses, or the at least one support includes on its internal cylindrical surface in contact with the liquid, one or more recesses.

In a rotor in rotor configuration, a pump has inward projections on an outer rotor and outward projections on an inner rotor. The outer rotor is driven and the projections mesh to create variable volume chambers. The outer rotor may be driven in both directions. In each direction, the driving part (first inward projection) of the outer rotor contacts a sealing surface on one side of an outward projection of the inner rotor, while a gap is left between a sealing surface of the other side of the outward projection and a second inward projection. The gap may have uniform width along its length in the radial direction, while in a direction parallel to the rotor axis it may be discontinuous or have variable size to create flow paths for gases.

A variable displacement gear pump comprises a fixed gear, a movable gear movable, a fixed gear ring fitted over the movable gear, a movable gear ring fitted over the fixed gear, a fixed cover having a hole in which the fixed gear ring rotates, a movable cover having a hole in which the movable gear ring rotates, a fixed gear block attached to the fixed cover, and a movable gear block attached to the movable cover. The fixed gear is engaged with the movable gear. The movable gear ring rotates in the hole of the movable cover, and the fixed gear ring rotates in the hole of the fixed cover. The movable gear, together with the movable cover, the movable gear, and the movable gear block, move along the direction of the shaft to change a width in which the fixed gear is engaged with the movable gear.

A pump drive for conveying a reducing agent for motor vehicle exhaust gas systems, with an electronically commutated direct current motor, a positive displacement pump, and a freezing compensation structure. Also, a modular motor and pump family for forming different pump drives with several such electric motors and pumps. It is the aim of the invention to ensure, in the simplest and most robust manner possible, the integration of a hydraulic unit (gear pump) into an electrical unit (electric motor), a sealing of a wet region from a dry region, an integration of a freezing compensation into the wet region, and a mechanical attachment on the customer side. A modular construction of the electric motor and of the positive displacement pump, which, without a large modification cost, via simple combination of assemblies or modules, can be used for different requirements, is important for this.

A laundry treatment apparatus is disclosed. The laundry treatment apparatus includes a tub provided in a cabinet for storing water, a water supply unit for supplying water to the tub, a drum rotatably provided in the tub for storing laundry, a first pump including a first housing for receiving water discharged from the tub and an impeller rotatably provided in the first housing for discharging the water introduced into the first housing out of the first housing, a drainage pipe configured to extend through a height higher than the maximum possible level of water in the tub for guiding the water discharged from the first housing out of the cabinet, and a second pump including a first gear and a second gear rotatably provided in a second housing, into which the water discharged from the tub is introduced, the second pump being configured to move the water introduced into the second housing to the drainage pipe when the first gear and the second gear are rotated.

A fluid delivery device having a forepump and a main pump fluidically connected to the forepump, wherein the forepump can be driven via a forepump input shaft and the main pump can be driven via a main pump input shaft. According to the invention, the forepump has a forepump drive gear coupled to the forepump input shaft and a forepump delivery gear interacting with the forepump drive gear to deliver the fluid, wherein the forepump and the main pump are drivingly coupled to a common drive shaft, and wherein the forepump delivery gear and the main pump input shaft are connected to one another via a connecting shaft such that the forepump input shaft is coupled directly to the drive shaft and the main pump input shaft is coupled to the drive shaft via the connecting shaft.

A gear set for an internal gear machine. Both front areas of the first gearwheel include respectively one running area, which are axially spaced apart by a first gearwheel thickness, and the second gearwheel includes a thickness-reduced region which has a reduced gearwheel thickness in relation to the first gearwheel thickness.

A crescent member is disclosed which is configured to be in constant contact with outer and inner gear teeth to prevent unwanted fluid backflow between the gears. The crescent member may be part of a low-pressure fuel pump system for a diesel engine. In order to reduce heat buildup in the crescent member and gear teeth, the crescent member comprises a gap to allow fluid to flow within the crescent member to absorb and dissipate the heat generated by friction. The crescent member is resilient to maintain constant contact, but flexible enough to reduce wear from friction over time.

A gear pump comprises an internal gear (10), a first external gear (20) and a second external gear (30), a case member (50) having a one end side accommodation portion (52) for retaining these gears (10,20,30), an other end side accommodation portion (53) at other end side and a partition wall portion (54) therebetween, a cover member (70) and a plate member (80). A pump chamber (P) defined inside the internal gear (10) is divided into a first pump chamber (P1) which has a first intake-discharge space (L1) and a first discharge-intake space (H1), and a second pump chamber (P2) which has a second intake-discharge space (L2) and a second discharge-intake space (H2). The plate member has a first communication path (81) and a second communication path (82) between the plate member (80) and the cover member (70). The one side communication passage (57) is communicated with the first communication path (81). Two penetrating holes (82b,82c) are formed on the plate member (80). An other side communication passage (82a), which communicate the two penetrating holes (82b,82c) with each other, is formed between the plate member (80) and the cover member (70).