Abstract: An impeller assembly for centrifugal pumps has two disk members that have different diameters, are arranged coaxially to a rotation axis and face each other so as to form an interspace; blades are radially arranged in the interspace; the two disk members are also centrally provided with a fastening means for fastening to a transmission shaft, which rotates about the rotation axis. The particularity of the present invention resides in having contoured vanes that protrude radially from the peripheral region of the disk member that has the smallest diameter and are arranged substantially at the blades.

Abstract: The present invention relates to a shaft coupling (also referred to as a spacer coupling) that couples a motor shaft and a pump shaft while both shafts are spaced from each other. The present invention is further relates to a pump apparatus having such a shaft coupling. The shaft coupling (10) includes: a first inner circumferential surface (23) capable of contacting an outer circumferential surface of a motor shaft (6); a second inner circumferential surface (24) capable of contacting an outer circumferential surface of a pump shaft (1); a step portion (26) protruding radially inwardly from the first inner circumferential surface (23) and capable of contacting an end portion of the motor shaft (6); and a spacer portion (28) located between the step portion (26) and the second inner circumferential surface (24).

Abstract: An impeller for centrifugal pumps has a first disk element, functionally arranged toward the inlet, which is coaxial to and faces a second disk element, which is functionally arranged toward the delivery and is connected rigidly to the first disk element by virtue of a series of angularly spaced vanes and is provided centrally with a means for fixing to a transmission shaft. The particularity of the present invention resides in that the impeller includes a series of openings formed in the substantially peripheral region of the second disk element, between pairs of adjacent vanes, substantially at the areas subjected to the greatest axial thrust.

Abstract: An impeller assembly for centrifugal pumps has two disk members that have different diameters, are arranged coaxially to a rotation axis and face each other so as to form an interspace; blades are radially arranged in the interspace; the two disk members are also centrally provided with a fastening means for fastening to a transmission shaft, which rotates about the rotation axis. The particularity of the present invention resides in having contoured vanes that protrude radially from the peripheral region of the disk member that has the smallest diameter and are arranged substantially at the blades.

Abstract: A motor assembly includes a motor, an inverter for changing rotational speed of the motor, a cooling fan coupled to a rotational shaft of the motor, a guide cover for guiding a gas flow generated by rotation of the cooling fan to the inverter, and at least two support members coupling the inverter to a side surface of the motor. The support members are located on both sides of a center line connecting a central axis of the motor to a center of the inverter as viewed from an axial direction of the motor. A space serving as a passage of the gas flow from the cooling fan is formed between the support members.

Abstract: A motor assembly (2) includes a motor (5), an inverter (6) for changing rotational speed of the motor (5), a cooling fan (8) coupled to a rotational shaft (10) of the motor (5), a guide cover (20) for guiding a gas flow generated by rotation of the cooling fan (8) to the inverter (6), and at least two support members (11) coupling the inverter (6) to a side surface of the motor (5). The support members (11) are located on both sides of a center line (C) connecting a central axis of the motor (5) to a center of the inverter as viewed from an axial direction of the motor (5). A space serving as a passage of the gas flow from the cooling fan (8) is formed between the support members (11).

Abstract: A pump has an impeller, a casing defining a pump chamber around the impeller for receiving a fluid discharged from the impeller; and, a seal mechanism provided between the impeller and the casing to prevent a fluid from leaking from the pump chamber through an annular space formed between the casing and the impeller. The seal mechanism comprises an annular seal member for blocking the annular space leaving an annular gap between the impeller and the seal member. The annular seal member is movably supported so that the annular seal member is supported in a floating condition in the fluid therearound in operation.