A liquid ring pump includes an external housing enclosing a volume including a lower fluid reservoir. A rotatable inner housing is within the volume of the external housing, the inner housing enclosing an inner fluid chamber. A pitot tube provides fluid communication between the lower fluid reservoir and the inner fluid chamber. The housings and pitot tube are adapted so that when the inner housing rotates, fluid flows from the lower fluid reservoir through the pitot tube into the inner fluid chamber to develop a liquid ring within the inner fluid chamber such that an inner radial wall of the liquid ring is just radially outward from a point where the pitot tube enters the inner fluid chamber.

A liquid ring pump includes an external housing enclosing a volume including a lower fluid reservoir. A rotatable inner housing is within the volume of the external housing, the inner housing enclosing an inner fluid chamber. A pitot tube provides fluid communication between the lower fluid reservoir and the inner fluid chamber. The housings and pitot tube are adapted so that when the inner housing rotates, fluid flows from the lower fluid reservoir through the pitot tube into the inner fluid chamber to develop a liquid ring within the inner fluid chamber such that an inner radial wall of the liquid ring is just radially outward from a point where the pitot tube enters the inner fluid chamber.

A rotor assembly for a centrifugal pump includes a rotor and a rotor cover, defining a fluid chamber therebetween, and having openings or channels that are provided in either the rotor cover or the rotor, or both, to direct fluid from the fluid chamber into the rotor or rotor cover of the rotor assembly to provide reduction of increased pressure that is experienced within the fluid chamber, especially at or near the center of the fluid chamber.

A rotor assembly for a centrifugal pump includes a rotor and a rotor cover, defining a fluid chamber therebetween, and having openings or channels that are provided in either the rotor cover or the rotor, or both, to direct fluid from the fluid chamber into the rotor or rotor cover of the rotor assembly to provide reduction of increased pressure that is experienced within the fluid chamber, especially at or near the center of the fluid chamber.

A fluid pump including an integrated pumping section and motor section may be achieved by a variety of techniques. In certain aspects, a fluid pump may include an integrated pumping section, motor section, and a control section that share structural components in order to reduce the structural material required for the complete device while simultaneously utilizing the integrated motor controller to enable the pump to operate at varying speeds other than the synchronous electrical power frequency that powers the device.

The multi-stage submersible pump at the exit side is provided with a non-return valve (9) including a valve seat (19) and a shut-off body (15) which is movably arranged thereto in a limited manner and which is arranged with a positive fit and in a movable manner within a guide (16) surrounding the shut-off body (15) with play. The inner contour of the guide (16) tapers inwards towards the valve seat (19), counter to the main flow direction (13).

The multi-stage submersible pump at the exit side is provided with a non-return valve (9) including a valve seat (19) and a shut-off body (15) which is movably arranged thereto in a limited manner and which is arranged with a positive fit and in a movable manner within a guide (16) surrounding the shut-off body (15) with play. The inner contour of the guide (16) tapers inwards towards the valve seat (19), counter to the main flow direction (13).

This invention relates to a cross-flow wave making pump comprising an impeller shell forming a water intake and a water outlet, an impeller assembly pivotally connected to two ends of the impeller shell, and a motor used for driving the impeller assembly; wherein, the impeller assembly comprises an impeller used for driving a liquid flow, a first turntable and a second turntable respectively fixed at two ends of the impeller, wherein the first turntable is provided with a shaft rotatably mounted in the impeller shell, the second turntable is provided with a cavity used for receiving a rotor shaft of the motor. The embodiments of the present invention can provide a sufficient liquid-circulation in a container, and significantly reduce the dead zone where the liquid flows extremely slowly. Other embodiments are disclosed.

This invention relates to a cross-flow wave making pump comprising an impeller shell forming a water intake and a water outlet, an impeller assembly pivotally connected to two ends of the impeller shell, and a motor used for driving the impeller assembly; wherein, the impeller assembly comprises an impeller used for driving a liquid flow, a first turntable and a second turntable respectively fixed at two ends of the impeller, wherein the first turntable is provided with a shaft rotatably mounted in the impeller shell, the second turntable is provided with a cavity used for receiving a rotor shaft of the motor. The embodiments of the present invention can provide a sufficient liquid-circulation in a container, and significantly reduce the dead zone where the liquid flows extremely slowly. Other embodiments are disclosed.

A fluid transfer coupling includes a first and second shaft assembly. The first shaft assembly includes a shaft and annular fin attached to shaft, annular fin having one or more internal passages extending therethrough. The or each internal passage connects a center portion of shaft to a radially outwardly facing side of annular fin. The second shaft assembly includes a shaft and annular trough extending radially outwardly of shaft. The first shaft is concentrically accommodated within second shaft with annular fin being accommodated within annular trough. In use, first shaft assembly rotates at a first rotational speed and second shaft assembly rotates at a second rotational speed, with second rotational speed being greater than first rotational speed. The difference between second and first rotational speeds cause a fluid contained within annular trough to be driven radially inwardly through the or each internal passage to center portion of first shaft.