Abstract: A flow by-pass system is provided in a downward-discharging exhaust hood of a steam turbine to by-pass a small percentage of the total steam flow from the top portion of the exhaust hood to the vicinity of the condenser and in that way relieve excess pressure in the top portion incident to the more convoluted path of the main portion of steam passing from the top to the bottom and to decrease energy loss caused by friction and thus to improve turbine efficiency. The flow by-pass system includes by-pass conduits within the front portion of the exhaust hood extending from the top portion to the vicinity of the condenser.

Abstract: A vacuum cleaner includes a driven impeller that moves working air for the vacuum cleaner. A first housing includes a first wall and a second housing includes a second wall opposite the first wall, and an outlet for the working air. The impeller rotates and draws the working air through an opening and directs the working air radially outwardly toward the first wall and then through an annular passage formed between the first wall and the second wall. The annular passage restricts the flow of working are to provide back pressure on the impeller.

Abstract: A blowing fan assembly for a window-type air conditioner which includes a scroll case and a turbofan disposed in the scroll case and connected with a driving motor, the turbofan having a hub, a plurality of blades which are located at a predetermined separation from the hub, and a shroud which is attached to distal ends of the plurality of blades in opposition to the hub. A depression is formed at the rear wall of the scroll case in a manner such that the diameter of the depression is greater than an outer diameter of the turbofan, and the turbofan is lop-sidedly positioned in the scroll case in such a way as to adjoin the depression, whereby the air passage which is defined between the shroud of the turbofan and a suction opening of the scroll case, is increased.

Abstract: A vacuum cleaner includes a driven impeller that moves working air for the vacuum cleaner. A first housing includes a first wall and a second housing includes a second wall opposite the first wall, and an outlet for the working air. The impeller rotates and draws the working air through an opening and directs the working air radially outwardly toward the first wall and then through an annular passage formed between the first wall and the second wall. The annular passage restricts the flow of working are to provide back pressure on the impeller.

Abstract: A furnace blower housing has a two-piece exhaust transition, one piece of which is an integral extension of the blower housing, that transitions a rectangular cross section outlet of the blower housing to a circular cross section outlet of the exhaust transition that is adapted to be attached to a circular exhaust pipe.

Abstract: The invention relates to a radial split diffuser with an inner casing and an outer casing joined together along a cylindrical joint. Each diffuser passage is intersected by and extends transversely across the joint. The advantages of this design include: the elimination of a transition within the initial portion of the passages where air flow speeds are supersonic and minute surface discontinuities can significantly effect performance; and the simplification of manufacturing through use of metal castings to replace sheet metal fabrications in the manufacture of diffusers. The joint in the present invention can be located downstream from the diffuser inlet a sufficient distance in a lower velocity area. The joint is located to enable access for precise machining of the critical initial portion of the passages within the inner casing, and to minimize air flow disturbance in the initial portion.

Abstract: A centrifugal blower comprising a siroco fan having a plurality of blowing fans, and a scroll casing forming a spiral draft passage at an external side of the siroco fan, where a siroco fan is so mounted that spiral centers (02,03) comprising the draft passage of the scroll casing are detached from a center (01) of the siroco fan at a predetermined distance, such that a spiral curve of the scroll casing is simply changed to a non-linear curve to thereby enable to increase a flow rate even at a low revolution of the siroco fan and to reduce noise.

Abstract: A sirocco fan which reduces abnormal noise and improves air flow includes: a scroll 2 with an inlet wall 8 and a closed endwall 9, the inlet wall 8 having an inlet and the endwall 9 being opposed to the inlet wall 8; and an impeller 3 provided in the scroll 2, for suctioning and exhausting air, wherein a cutoff 7 of the sirocco fan 1 is inclined so as not to allow entire sections of a blade 10 of the impeller 3 to be simultaneously met entire sections of the cutoff 7 when the blade 10 of the impeller 3 passes through the cuttoff 7, thereby achieving stable air flow.

Abstract: The removal of cooling air from the diffuser part of a radial stage of a compressor of a gas turbine is provided. The end stage of the compressor has a radial rotor disk (2) with a bladed diffuser (3). With the corresponding fastening elements (7) for the parts (20.1, 20.2) on the diffuser housing side, the diffuser blading (3) is used at the same time to connect the vane support (1) to the rear bearing housing (21). Compressed cooling air can be removed through either/both round holes (6.1) or/and slots (6.2), which are milled on the suction side of the diffuser vane (3). Through the removal openings (6.1, 6.2), the cooling air enters the blind holes (19) of the diffuser vane (3) and then further, through holes (19.1) in the diffuser housing outside (20.2), the cooling air discharge (10) arranged in the compressor housing.

Abstract: An air pump includes a housing having a top formed with a circular recess, a first semi-cylindrical member in communication with the circular recess, and a first curved baffle arranged close to the first semi-cylindrical member, an electric motor mounted within the housing and having an output axle extending upwardly out of the center through hole, a bottom cover engaged with a bottom of the housing by retainers, a centrifugal impeller eccentrically fitted in the circular recess so that there is a circular passage between the centrifugal impeller and an inner wall of the circular recess, an upper cover configured to engage with the circular recess to cover the centrifugal impeller and having a conical portion disposed above the centrifugal impeller thereby forming a passage therebetween, whereby the air pump can provide sufficient air pressure to inflate an object in a short time.

Abstract: A centrifugal blower assembly for a heat exchanger system of an automotive vehicle is described. The centrifugal blower assembly includes a diffuser section interposed between the centrifugal blower housing and a heat exchanger housing in the heat exchanger system. The diffuser section has a pair of non-linear, curved side walls which allow for expansion of the air flowing therethrough to minimize air flow separation against the side walls of the diffuser.

Abstract: A housing for a double spiral circulation pump includes a spiral housing and a multipartite rib. The spiral housing defines a flow channel. The multipartite rib is disposed in the housing to divide the flow channel. The multipartite rib includes at least two rib parts spaced from each other to define a gap therebetween.

Abstract: The angular extent of the flow path in a fan scroll is extended by reducing the rate of radial expansion of the flow path. By extending the angular as circumferential extent of the scroll flow path downstream of the fan impeller ANC structure can be located in/on the scroll while being located a sufficient distance downstream of the impeller. The flow path length can be increased without increasing the cubage of the scroll and, if desired, a further flow path increase can be achieved by a combination of the reduced rate of radial expansion together with increasing the cubage.

Abstract: If rotor blades have such form that between them are formed channels which have between their inlets and outlets a narrow cross section, then when the rotor rotates a fluid flowing from the inlet into the narrow cross section accelerates reaching there an increased velocity which is so directed that the reaction of fluid's momentum drives the rotor. The rotor then generates power consuming the fluid's mechanical energy. When the fluid flows from the narrow to increasing cross section of the channel, the momentum is absorbed by the downstream increasing the fluid's pressure. The fluid thus converts its own heat directly into its mechanical energy which equals the sum of the energy which drives the rotor and the kinetic energy of the fluid issuing from the channels, whereat the fluid issuing from the channels is correspondingly cooled.

Abstract: A drainage pump has a pump body, a vane, a ring, and a circumferential wall. The pump has a cylindrical small vane pump chamber and a large vane pump chamber extending from and communicating with the small vane pump chamber. A suction inlet communicates with the small vane pump chamber and a discharge outlet communicates with the large vane pump chamber. A chamber slope portion is formed between the small vane pump chamber and the large vane pump chamber. The vane is adapted to be driven by a motor and is rotatably mounted to the pump body. The vane includes a large vane portion received in the large vane pump chamber and a small vane portion extending from the large vane and received in the small vane pump chamber. The small vane portion and the large vane portion rotate together when driven by the motor. A vane slope portion is formed between the large vane portion and the small vane portion. The ring has a central opening, positioned between the large vane portion and the small vane portion.

Abstract: In a gas turbine having a transition region between a combustor and turbine stage including a transition piece duct extending between a combustor liner and the turbine stage; an impingement sleeve surrounding the transition piece, the impingement sleeve having a plurality of apertures therein; and a compressor diffuser directing compressor discharge air into the transition region, an improvement wherein the diffuser includes a pair of outer walls flaring outwardly in a direction of compressor discharge air flow; and a pair of baffles within a flow area defined by the pair of outer diffuser walls which divide the flow area into three discrete flow passages. One passage has a substantially radial flow component; a second passage has both radial and axial flow components; and a third passage has a substantially axial flow component.

Abstract: In a diffusor for an axial-flow steam turbine with an axial/radial diffusor, the kind angles Of the diffusor inlet both at the hub and at the cylinder of the turbo-machine are determined solely for the purpose of equalizing the total pressure profile over the channel height at the outlet of the last blade row. The diffusor is subdivided from the inlet to the outlet into an inner and an outer channel by a radially outward-curved guide plate. Within the deceleration zone of the diffusor, radial-flow flow ribs are arranged in the outer channel and diagonal-flow flow ribs are arranged in the inner channel for canceling the rotation of the rotational flow.

Abstract: In a diffusor for an axial-flow steam turbine with an axial/radial diffusor, the kink angles of the diffusor inlet both at the hub and at the cylinder of the turbo-machine are determined solely for the purpose of equalizing the total pressure profile over the channel height at the outlet of the last blade row. The diffusor is subdivided from the inlet to the outlet into an inner and an outer channel by a radially outward-curved guide plate. Within the deceleration zone of the diffusor, radial-flow flow ribs are arranged in the outer channel and diagonal-flow flow ribs are arranged in the inner channel for canceling the rotation of the rotational flow.

Abstract: A pump casing made of sheet metal comprises a casing jacket having a cylindrical cup shape, an end plate formed at one side of the casing jacket, a casing flange formed at the other side of the casing jacket and a projecting portion radially outwardly bulged so as to have a volute shape. The end plate is axially outwardly bulged so as to have an arcuately curved surface, and the base portion of the projecting portion is located on the extension of the arcuately curved surface of the end plate so as to provide continuity from the end plate to the projecting portion. With the above structure, there is no portion where a great deal of bending stress caused by stress concentration is generated, and the pump casing has a sufficient strength and rigidity against not only piping forces but also internal pressure.

Abstract: A collector for a vaned diffuser in a centrifugal compressor, wherein the radial cross-sectional area of the collector housing at the entrance to the collector outlet duct is 40% to 80% of the entrance area of the outlet duct and progresses smoothly to the outlet duct entrance area. Progression in collector housing cross-sectional area is produced by variation of the collector axial height. At the intersection with the outlet duct, the collector has a step in axial height so as to at least partially direct circumferential flow from the collector into the outlet duct entrance.

Abstract: A compact centrifugal fan that draws air in past the impeller hub, which encloses a motor and which spins about a central axis, and then urges the air through a bend in the fluid passageway. As the air passes through the annular inlet channel about the impeller hub, it flows in a forward axial direction. The air passes through the bend in the fluid passageway, as the air is being swept around the hub by the blades of the impeller. After the air passes through the bend, it has a reverse axial flow component, in addition to a circumferential flow component. Air having a forward axial flow component passes by the portion of an impeller blade that is closest to the impeller hub, and air having a reverse axial flow component passes the portion of a blade that is furthest from the impeller hub.

Abstract: A pipe diffuser is used in a centrifugal compressor in such a way as to obtain high efficiency over a broad operating range. The number of channels in the pipe diffuser is limited such that the wedge angle is relatively large and therefore not susceptible to flow separation at the leading edges thereof. The vaneless space between the impeller and the leading edge circle of the diffuser is limited in its radial depth such that the flow separations are further inhibited. Finally, the impeller has a relatively high backsweep such that the absolute flow exit angle is relatively low, thereby reducing the sensitivity to lower flow conditions.

Abstract: A diffuser of a centrifugal compressor for guiding a fluid flowing from an impeller to a scroll. The diffuser is formed by a pair of oppositely disposed lateral walls. The diffuser is provided at a fluid outlet portion thereof with an outlet throttling portion. This outlet throttling portion is formed by gradually narrowing the passage width downstream from a starting point which is located in a position at which the fluid dynamic pressure is almost perfectly changed to a static pressure. The provision of the outlet throttling portion decreases the risk of a pressure loss, restrains the possibility of flow separation and prevents the fluid from reversely flowing from the scroll. This results in improvements in surge line and partial load efficiency.

Abstract: A supersonic centrifugal compressor comprising an impeller (2), a plurality of vanes (13) radially extending in the impeller to form a plurality of radially extending flow channels therebetween, and a diffuser (3) circumferentially surrounding the impeller and having a circumferential flow channel communicating with the flow channels of the impeller. In the impeller (2), at least one nozzle (18) is provided at the outlet of the flow channel and a contraction (20) is provided at the inlet of the flow channel, so that the flow channel is a low speed flow channel (21). Thus the speed of the fluid is low in the low speed flow channel (21) and high at the outlet of the nozzle (18). Also, in the diffuser (3), backflow preventing and friction reducing projections (33) are provided concentrically in the inner surface of the casing (11).

Abstract: An apparatus for separating and recovering floating liquid wherein one or more vortex guide plates are horizontally held on the surface of the water inhibiting their rotation, the lower members of the guide plates are submerged under the surface of the water, an enveloping cylinder at the center of vortex has its upper end suitably positioned under the surface of the water and has its lower end submerged deeper than the peripheral guide members, a suction tube for recovery is provided in said cylinder, a rotary impeller is provided under said cylinder in concentric with the vortex guide plates and is rotated in the enfolding direction of the vortex guide plates, and wherein a cylindrical cover is provided between said guide plates and said impeller, said cylindrical cover having an opening in the upper end surface thereof with its diameter being smaller than the diameter of the impeller and further being open at its lower end.

Abstract: A pump has an impeller with a circular series of airfoil vanes rigidly mounted thereon. The impeller is mounted in a casing which has a radially outwardly increasing internal axial extent, such that fluid flowing through the pump has a less constricted path peripherally of the pump chamber than centrally of the pump chamber. In another aspect of the invention, the impeller comprises two axially adjacent series of vanes separated by a radially extending partition which divides the interior of the pump casing into a vacuum chamber and a pressure chamber interconnected by a hole formed in the center of the partition. At least one of the central partition and the impeller plate are conical in shape, thereby to impart a radially outwardly expanding axial extent to the vacuum chamber, and a decreasing axial extent to the pressure chamber.

Abstract: This invention relates to a centrifugal pump, bearing housing, diffuser ring, and volute housing fastening arrangement in which a plurality of containment pump bolts pass through, in one direction, corresponding openings in the bearing housing, the diffuser ring, and the volute housing, whereas gear box mounting bolts pass through in an opposite direction corresponding openings in the bearing housing, the diffuser ring, and the volute housing. The mounting bolts are secured in a portion of a gear box. The mounting bolts therefore provide a function of providing pressure containment for the pump in the event that a containment pump bolt or fastener is missing or ineffective, in which case a load carried by a missing pump bolt is carried by a nearby mounting bolt. The containment pump bolts, having bolt heads adjacent the gear box, to prevent inadvertent torquing during routine maintenance.

Abstract: Liquid pump assembly comprising a pump housing having a pump chamber, a drive shaft in the pump chamber mounting a pump rotor, a pump chamber cover and a molded member (12,18) partially defining the shape of the pump chamber (8) located on the inside surface of the pump cover (1).

Abstract: The metal plate stator case (1), for radial centrifugal pumps, includes a main body (2), a diffusion volute (10), an axial suction inlet (3) and a radial discharge outlet (4) at the output of the diffusion volute. The volute is constituted by a circumferential channel (11) which is defined in the lateral wall of the main body and has a radial transverse cross section which increases uniformly toward the output of the volute. At least one portion of the channel has, in transverse cross section, a substantially constant radial depth and a uniformly increasing axial width.

Abstract: An apparatus for the heating of air with a series of compression and expansion stages. The heating system includes four primary stages, centrifugal turbine compression, expansion through diffusing vanes, expansion into a low pressure chamber and nozzle compression. The thermal energy transferred to the air during these compression and expansion stages is of a degree to omit the need for a heat exchanger. The turbine compression stage heats and compresses the air significantly, while the following three stages convert this very high pressure and temperature air to a level that allows the air to be directly discharged into standard heating ducts. The diffusing vanes decrease the velocity of the air discharged from the compression turbine and the expansion chamber lowers the pressure to sub atmospheric pressure. The final stage compresses the air to standard atmospheric pressure and compensates for the heat lost in the expansion chamber.

Abstract: A pump casing manufactured by press forming of steel plate and including a volute casing encircling a pump impeller so as to form a fluid path around the pump impeller is disclosed. The cross-sectional area of the fluid path is gradually increased towards a discharge port of the pump casing. The pump casing includes a casing body which is formed at first by press forming a metal plate into a cylindrical cup shape having an opening portion at one side thereof and a closed bottom portion at the other side of the same, and then by press forming the cylindrical cup shaped casing body so as to have a volute portion radially outwardly expanded from a cylindrical surface of the casing body at an axially intermediate portion thereof which radially opposite to the pump impeller, a casing flange outwardly extending from the opening portion and an aperture serving as a suction port at the bottom portion.

Abstract: A centrifugal pump having a two member casing in which a first member with a circular peripheral inner wall incorporates a discharge branch and the other member is shaped in such a way as to determine the shape of the volute of the pump when the two members are brought together. The first casing member has a flange extending transversely from the peripheral wall. The second casing has a flat surface for abutment against the flange to seal the two members. The second casing member has a centrally raised section in which the radius of the section varies circumferentially so that the flow area of the volute of the pump varies circumferentially within the pump.

Abstract: A diffuser for a radial flow compressor includes a pair of coaxial rings, the second of which closely surrounds the first. A set of intersecting flow passages extends through the first ring, and another aligned set of flow passages extends through the second ring. In a first embodiment of the invention, a circumferential groove is formed between the two rings, thus allowing low momentum fluid to migrate from the pressure side of one passage to the suction side of a neighboring passage and to prevent boundary layer build-up. In a second embodiment of the invention, the passages are arranged in a double cone configuration which allows higher diffusion levels than are attainable in a straight cone diffuser of equal length.

Abstract: The radially compact fluid compressor especially suitable for use in the distillation apparatus or other environments where space may be at a premium is disclosed herein. The compressor includes a power driven impeller and a compressor housing which surrounds the impeller and which together with the impeller defines a fluid collection chamber extending between the first upstream end and a second fluid exiting downstream end. This collection chamber progressively enlarges vertically from its upstream end to its fluid exiting downsteam end, whereby fluid passing through the collection chamber from its upstream end to its downstream end progressively decreases in velocity and therefore progressively increases in static pressure.

Abstract: A centrifugal compressor having a two section diffuser which has a tapered section having a constant diffusing area along its radial length, and a straight section having an increasing diffusing area along its radial length, and a diffusing volute having a throat area significantly larger than conventional designs.

Abstract: The present invention provides a curvilinear transition duct for use with a centrifugal fan that affords optimal fan efficiency without undue duct length. The duct comprises a top section of generally concave planar shape when viewed from above and a bottom section. Side sections join the top and bottom sections to form a four sided structure having an inlet opening at one side and an outlet opening at the other side. The preferred bottom section is of a generally longer longitudinal length than the top section. Further, the preferred duct has a plane in contact with the edges of the inlet opening which intersect a plane in contact with the outlet openings at a level above the duct. The angle formed between the planes would be 1.degree. to 60.degree..

Abstract: A readily portable fan device which is usable both as a cooling fan for circulating ambient air and as a device for increasing the flow of air through a register, comprises a housing containing both a fan impeller and an electric motor for driving the impeller, the housing having a skirt surrounding a bottom air inlet and capable of at least partially sealing a space around such register, the fan directing air upwardly through an outlet aperture when resting on the skirt. The device has another floor engaging surface perpendicular to the plane of the skirt on which the device may rest with its air inlet open to the ambient air. The impeller blades and the outlet aperture are specially designed to maximize air throughput.

Abstract: An axial-flow fan, particularly a small fan which is axially compact, with a scroll plate surrounding the impeller and whose inner contour has a cylindrical configuration in the vicinity of the axial median plane and extends both towards the inlet side and the outlet side in a polygonal, particularly square profile accompanied by the formation of corner areas, and with a central, coaxial core formed by the drive motor, the impeller hub and the mounting flange for the drive motor; the core thereby has an annular surface conically tapering towards the inlet side face whose axial length is at least one-third of the hub length; with respect to the axial median plane, the scroll plate is asymmetrical in the corner areas and is made cylindrical over a longer distance from the axial median plane to the inlet side than to the outlet side.

Abstract: An axial fan arrangement is provided, especially for the radiator of a water cooled internal combustion engine for commercial vehicles. In order to reduce noise levels without impairing fan efficiency, an air guide structure is provided which widens in the flow direction starting from adjacent the air inlet edges of the fan blades. Embodiments are included which have part of the air guide structure carried by the fan blades and other embodiments have fixed air guide structure. The contour of the air guide structure conforms to the facing contour of the fan blades.

Abstract: A device for controlling the flow pattern of the exhaust gas of a supercharged internal combustion engine comprises a diverging conduit disposed at the outlet of an exhaust gas operated centripetal turbine, a radially finned conduit portion, a converging conduit and an exhaust pipe for conveying the gas to atmosphere. The back pressure at the engine exhaust is thus minimized.

Abstract: A draft tube for discharging fluid from a hydraulic turbine is disclosed as having a draft tube wall surrounding a discharge passage which diverges from a turbine runner to a discharge opening. The draft tube includes a first region downstream of the runner which has a rate of divergence less than that at which boundary layer separation occurs. A second region, downstream from the first region, has a rate of divergence greater than that at which boundary layer separation normally occurs. The draft tube wall surrounding the second region is provided with a plurality of orifices. A plurality of nozzles are provided on the draft tube wall surrounding the first region. Piping connects the orifices with fluid inlets of the nozzles. The nozzles have fluid outlets which communicate with the discharge passage in the first region and open away from the turbine runner. Fluid along the wall in the second region passes through the orifices and piping and into the nozzles.

Abstract: An axial fan, preferably for the cooling systems of water-cooled internal combustion engines, comprises an impeller and an air duct housing provided with a fan guard which is separated by an annular gap from the tips of the impeller blades and is centered on the impeller axis by a support comprising radial arms attached to the fan guard. For noise reduction, the radial arms are supported on the hub of the impeller, on the side facing the fan shaft, by means of a roller bearing held by a mounting plate, and the mounting plate is made independent of the impeller bearing.

Abstract: A stall-free axial flow fan (10) has an impeller (12) with a plurality of radially extending blades (14) enclosed in a tubular casing (11) divided into a inlet portion (15), an intermediate portion (16) of larger diameter than the minimum diameter of the inlet portion (15) and an outlet portion (17) of a diameter no larger than the minimum diameter of the inlet portion (15). Impeller (12) is positioned with the leading edge of each blade (14) protruding into the intermediate portion (16) and the trailing edge protruding into the outlet portion (17). Inlet portion (15) may contain a plurality of radially extending vanes (19) each rotatable about a spindle (20) and extending between the stator (18) and the inner wall of the inlet portion (15). Intermediate portion (16) may contain a plurality of fixed vanes (21) disposed radially of the stator (18) and axially of the casing (11).

Abstract: Owing to a new design of the partition wall (vortex former) of the novel type tangential blower, there is achieved an improvement of the pressure-volume characteristic and a reduction of the noise development.

Abstract: A diffuser for augmenting a wind turbine having means for energizing the boundary layer at several locations along the diffuser walls is improved by the addition of a short collar extending radially outward from the outlet of the diffuser.

Abstract: A guide blade set for diverging jet streams in a steam turbine which has blades (2, 2') whose concave and convex surfaces are orthogonal firstly to the jet stream floor plate (3) and secondly to the jet stream passage ceiling plate (4) at their respective ends.Efficiency is improved by reducing losses in the neighbourhood of the jet stream ceiling plate.

Abstract: A centrifugal pump assembly comprising one or more bowl castings each housing an impeller and also two or more individual fluid passageways for the flow of fluid discharged by an impeller to the next impeller, the passageways having some exterior walls defining the exterior of the assembly. By changing the number of the individual passageways, the specific speed of the pump, i.e., the ratio of the amount of energy imparted to the fluid and the amount of fluid being pumped, can be changed.

Abstract: A fireplace unit provided with a fan below the bottom wall of the fire box for circulating room air around the fire box.

Abstract: A centrifugal pump comprises a casing which has two volutes disposed substantially diametrically opposite each other in such a way that the end of the first volute is adjacent to the start of the second volute. The outer diameter of the casing approximates or equals the diameter of the first volute in the region of the end of the first volute. This contributes to compactness of the casing. The volutes surround a rotary impeller or a guide wheel which is installed in the casing downstream of the impeller. Each volute extends along an arc of at most 180 degrees. The casing can have one or more elongated channels extending from the end of the first volute, along the second volute, and to a common outlet nozzle for both volutes.

Abstract: The invention relates to a construction of the housing and arrangement of the rotor of a self-priming centrifugal pump whereby the suction from the suction part is carried out by means of the stator so that there has been eliminated the need for the suction part of the pump to be filled up with liquid prior to the pumping operation.