Abstract: A centrifugal pump device has at least one impeller (16), a circulation connection between a delivery side (22) of the at least one impeller (16) and a suction side (20) of the at least one impeller (16), and a valve arrangement (30, 46) in said circulation connection (44, 54). The valve arrangement (30, 46) has a first valve mode providing a pressure dependent shut-off valve (46) in the circulation connection. The valve arrangement (30, 46) allows a change between the first valve mode and at least one further valve mode. The at least one further valve mode provides at least one fixed closing degree of the circulation connection (44, 54).

Abstract: A self-priming assembly for a multi-stage pump is provided. The self-priming assembly can have a first diffuser, a second diffuser, and an impeller. The first and second diffusers each include a central portion, a diffuser axis, an arcuate channel within the central portion, and a passage extending through the central portion. The first diffuser and the second diffuser are configured to be combined and receive the impeller therebetween with the first diffuser axis, the second diffuser axis, and the impeller axis aligned.

Abstract: A multi-stage, self-priming centrifugal pump assembly includes at least two pump stages (4) which are consecutive in a main flow direction (32), and a backflow channel (13) which lies parallel to at least one a pump stage (4). The backflow channel (13) runs out downstream of the first or a further pump stage (4), in the main flow direction (32).

Abstract: A pump unit 12 includes a pump housing 14, a pump cover 16, and an impeller 18 between the pump housing and pump cover. The pump housing and pump cover define a first channel 32 and a second channel 34 each having an inlet and an outlet. The impeller has first vanes 36 cooperating with the first channel and second vanes 38 cooperating with the second channel. The outlet of the second channel is constructed and arranged to provide fuel to an engine upon rotation of the impeller. A jet pump 38 is fluidly connected with the outlet of the first channel such that as the impeller rotates, the jet pump causes fuel to be drawn into the reservoir 37. Connecting structure 44 fluidly connects the first and second channels such that upon rotation of the impeller, fuel in the second channel flows into the first channel to prime the first channel.

Abstract: A device (1), for evacuating a chamber to pressures in the high vacuum range includes a suction-side vacuum pump (2) and an atmospheric-pressure-side vacuum pump (3). The suction-side vacuum pump (2) is a mechanical kinetic vacuum pump with a rotor (11) and a stator (10). The stator (10) has a rotationally-symmetrical inner surface which matches the outer rotor geometry. The rotor (11) in the mechanical kinetic vacuum pump (2) is provided with a structure (13) carrying out the gas pumping. Said gas pumping structure comprises webs (14), the angle and width of which decrease from the suction side to the pressure side. The gas throughflow is improved. The outer diameter of the rotor (11) and the inner diameter of the stator (10) of the suctnion-side pump decrease from the suction side to the pressure side.

Abstract: A submersible pump assembly has a pump and a valve connected to the outlet of the pump. An outlet of the valve is connected to a riser. A valve member in the valve housing is vertically movable between a pumping position and a priming position, the valve member being biased toward the priming position. A priming conduit connects the outlet of the valve housing to the inlet of the pump for directing well fluids flowing through the conduit into an intake of the pump for re-priming the pump. When the pump is pumping well fluid, the valve member is moved to the pumping position by the fluid pressure, well fluids flowing from the inlet of the valve housing to the outlet of the valve housing but not through the priming conduit. When pumping ceases, the valve member returns to the priming position, well fluids flowing through the priming conduit for re-priming the pump.

Abstract: The present invention relates to an improved fluid handling system including an improved collection trough and pump assembly. A centrifugal pump is mounted in the path of cutting fluid that needs to be pumped from a collection system and discharged. A wide and narrow inlet mouth lies very low on the factory floor enabling the centrifugal pump to be mounted right on the floor and not within the floor. An optional vacuum system provides suction within the centrifugal pump that aids in priming the pump at start up and in removing air from a pump chamber within the pump, thus allowing more efficient pumping to take place. An impeller rotates within the pump creating a vortex within the pump chamber which facilitates movement of dirty cutting fluid including metal particles to be pumped through to a discharge outlet.

Abstract: A pump has a housing defining a pump chamber and having a shaft opening. An impeller shaft extends through the shaft opening and is sized to define a gap between the impeller shaft and the shaft opening. An impeller is attached to the shaft inside the pump chamber. The impeller includes a first set of impeller blades for transporting fluid through the pump chamber and a second set of impeller blades for creating a pressure force which pushes fluid away from the shaft opening. The pump with sealless shaft prevents fluid from leaking through the gap, and therefore is particularly suited for use in a tank-type vacuum cleaner capable of collecting both dry material and fluid. The gap is used in such an application to prime the pump, thereby discharging fluid collected in the tank.

Abstract: The present invention provides a drain pump for a washing appliance. The pump includes a motor having a drive shaft, a drain pump impeller mounted on the shaft, and a pump casing having a side wall which is co-axial with the motor and the impeller, which is adapted to receive water from a wash chamber. The impeller pumps water from the casing when the motor is rotated in a first direction. The pump includes a disc, the periphery of which is adjacent to the wall of the casing to form a seal against fluid flow up a side of the casing. The disc has a hub portion and blades formed on a surface thereof with a root of each blade radially spaced from a periphery of the hub portion over the full height of the blade to form an unimpeded annular fluid passage between the hub portion and the blades.

Abstract: Centrifugal pump with a pump chamber (18) housing a radial impeller (20) and aspiration port arranged coaxially with the radial impeller, and at least one ventilating conduit (26) that leads from the inner radial area of the pump chamber to the outside, wherein the outer circumferential edge of the pump chamber (18) is fitted with interference contours (32) that are essentially directed tangentially to swirl the liquid flow.