Abstract: The pump comprises a pump body and a volute, mutually complementary with respect to one another, which once assembled form a waterproof container within which a permanent magnet rotor and an impeller are contained respectively in a first and in a second chamber. The stator part of the electric motor is provided externally to said waterproof container, and thus can never be affected by the liquid. The introduced improvements relate to the coupling between impeller and rotor and to the means adapted to make the rotor chamber waterproof, so that there cannot enter therein foreign matter, and in particular metallic dust, which by remaining associated with the permanent magnet of the rotor would prevent the rotation thereof, blocking its operation.

Abstract: The filter device comprises a filter chamber, a water supply chamber associated with the filter chamber and an aspiration tube, having a first and inserted in the water supply chamber and a second end which is immersable in an aquarium. The device also comprises a centrifugal pump adapted for feeding water to the filter chamber, and an impeller housed in an impeller chamber having an aspiration port, whereon the first end of the aspiration tube is selectively positionable. The impeller is associated with a permanent magnet rotor contained in a watertight cylindrical body, externally embraced by a cluster of stator windings. The filter chamber has a water outlet and houses a container adapted for accommodating filter elements.

Abstract: This invention relates to an electrically operated centrifugal pump of low power absorption for small or very small throughputs. The pump has a pump casing composed of at least two compartments and a cover which encloses an impeller chamber. A first compartment contains a pack of U-shaped laminations having a coil mounted on one arm and pole pieces which partially surround the second compartment. The latter includes a transversely magnetized permanent magnet rotatably supported on a fixed coaxial shaft. The impeller is coupled to one end of the magnet support which projects from said second compartment.