An electric pump includes a pump portion including a pump housing and a gear pump which is housed in the pump housing, the pump portion suctioning and discharging a hydraulic fluid by a rotation of the gear pump. The electric pump also includes a motor portion arranged adjacent to the pump portion in a direction along an axis of the pump portion and including a rotor which rotates synchronously with the gear pump and coaxially with the axis, the motor portion including a stator which is arranged at an outer periphery of the rotor and disposed coaxially with the axis, the stator applying a rotation drive force to the rotor. The electric pump further includes a resin portion integrally surrounding at least an outer periphery of the pump housing and an outer periphery of the stator.

Provided is an internal gear pump. The shape of any one of a plurality of external teeth and a plurality of internal teeth of the pump is formed on the basis of formulae (1)-(5). Formula (1): r = ro - dr · cos θ, Formula (2): Px = (ro - dr) + 1/4 dr {1 - cos (2θ)}, Formula (3): Py = 1/4 dr {-2θ + sin (2θ)}, Formula (4): Qx = Px - r · cos θ, Formula (5): Qy = Py + r · sin θ.

Die Erfindung betrifft ein Verschlusselement für eine Zahnradmaschine. Dieses hat zumindest eine Dichtplatte (28,30), die eine Niederdruck- oder Hochdrucköffnung (12) am Gehäuse (2) überdeckt und an diesem mittels eines Verbindungselementes (22) gehalten ist.

This invention relates to improvements in electric motor driven pumps, for example of the type used in hydraulic suspension systems for vehicles. In such a pump, the casing (3) of the motor is extended to include a chamber in which electronics can be housed. A lead-frame assembly (12) is described which retains and connects all the high power components. The casing may be split in order to define a pump rotor sub-assembly (1) and an electronics sub-assembly (2) which can be tested separately and then joined together by the use of simple interconnections.

Zwischen Pumpengehäuse (5) und Antriebsmotor (4) eines hydraulischen Kombiaggregats ist eine Flanscheinheit (6) angeordnet, welche einen das Pumpengehäuse (5) abdichtenden Dichtflansch (7) und einen einerseits am Dichtflansch (7) und andererseits am Antriebsmotor (4) lösbar befestigten Trägerflansch (8) aufweist. Trotz Beibehaltung einer günstigen direkten relativen Zentrierung zwischen Antriebsmotor (4) und Pumpe (1) kann damit eine montagefreundliche Vorzentrierung zwischen Trägerflansch (8) und Antriebsmotor (4) einerseits bzw. Trägerflansch (8) und Dichtflansch (7) andererseits vorgenommen werden. Unterschiedliche Kombinationen von Pumpe (1) und Antriebsmotor (4) können leicht durch Einsatz unterschiedlicher Flanscheinheiten (6) bzw. Trägerflansche (8) realisiert werden.

Traditionally the pump inlet and outlet ports are in a horizontal orientation. However, for some applications the ports of the pump are required to be in a vertical orientation.

A rotary pump assembly 1 comprises a rotary pump 2 and pump mounting means 4. The rotary pump 2 comprises a rotor containing assembly 6 and a gear containing assembly 8.

The rotor containing assembly 6 comprises a pair of inter-engaging piston/lobe rotors 10, 12 mounted for contra-rotation within a rotor case portion 7 about substantially parallel axes 13, 14; the rotor case portion is formed with an inlet port 9 and an outlet port 11 and comprises a circular cover plate 111.

Substantially parallel shafts 15, 16 also mounted for rotation about the axes 13, 14 respectively, are connected to the respective rotors 10, 12.

The rotors 10, 12 are secured on to the respective shafts 15, 16 by clamping/retaining nuts 17, 18.

The shafts 15, 16 extend from the rotor containing assembly 6 along the axes 13, 14 through the mounting means 4 and into the gear containing assembly 8.

The present invention provides a conventional hydraulic pump-motor (10) having an electric motor (12) coupled to a pumping mechanism wherein the motor includes an improved sound attenuating end shield design (34). Through the use of acoustically deadening materials such as cast iron and polypropylene plastic, the end plates (34) of the present invention deaden the sounds stemming from the vibration of the pump-motor. In addition, the present invention provides an end shield design (34) which allows the stator (16) to be secured to the motor housing (26) and the air gap (20) between the rotor (18) and the stator (16) to be precisely measured prior to the installation of the end shield. The present invention therefore results in not only a quieter pump-motor (10) but also a pump-motor (10) with higher machining tolerances, improved efficiency, and lower production and maintenance costs.

A gear metering pump (1) for delivering precise amounts of a compounded elastomeric material (2) into a die (3). The gear pump (1) has a housing (20) formed with a hollow interior chamber (21) containing a pair of rotating meshing gears (40,41) mounted on shafts (42,43), one of which is power driven, for passing controlled quantities of the compounded material out of the chamber and into the die (3). A side plate is removably mounted on the housing and encloses an open side of the chamber (21) and is moved between open and closed positions by fluid pressure cylinders (67) mounted on the housing to provide ready access into the chamber for cleanout. A first bearing assembly (34,35) for the gear shafts (42,43) is mounted on the removable side plate (30) and retains the gears (40,41) mounted thereon for removing the gears (40,41) from within the chamber (21) along with the side plate (30). Outlet openings (59,60,76,80,51) are formed in the removable side plate (30) and in an opposite fixed side plate (31) adjacent the shafts (42,43) and bearings (34,35,37,38), permitting small quantities of the compounded material (2) to flow between the shafts (42,43) and bearings (34,35,37,38) and out of the openings for lubrication of the bearings (34,35,37,38). The drive shaft passes out of the housing (20) through an enlarged opening and is free of any end seal with the housing to reduce heat buildup.

A gas removable pump for liquid comprising a housing having an inlet for introducing the liquid thereinto and an outlet for feeding the liquid therefrom, a drive shaft extending into the housing and having formed therein an axial bore, a rotary pump disposed within the housing, and a discharging chambor defined within the housing and separated from the rotary pump in a liquid-tight manner. The rotary pump includes a rotor secured to the drive shaft for co-rotation therewith and a plurality of cells for feeding the liquid, each cell constituting a separator for gas-rich liquid upon rotation of the rotor. A stationary shait extends in the axial bore between the rotary pump and the discharging chamber. A connecting arrangement is provided in the drive shaft and stationary shaft for selectively connecting each cell with the discharging chamber. Also provided is an ejector for ejecting into the discharging chamber the gas-rich liquid separated in the cells through the connecting arrangement. The gas-rich liquid gathers at inner portions of the cells due to a centrifugal force and is discharged by mesns of the ejector through the connecting arrangement.