Integrated centrifugal pump and motor

• US 5,158,440 A
• Filed: 11/08/1991
• Issued: 10/27/1992
• Est. Priority Date: 10/04/1990
• Status: Expired due to Term

• Current Assignee: Flowserve Management Company (Flowserve Corporation)
• Original Assignee: Ingersoll-Rand Company (Trane Technologies plc)
• Inventors: Bulson, Lee J., Cooper, Paul
• Primary Examiner(s): Bertsch, Richard A.
• Assistant Examiner(s): Basichas, Alfred
• Application Number:
  US07/793,237
• Time in Patent Office: 354 Days
• Field of Search: 417/423.1, 417/423.12, 417/423.4, 417/355, 417/356, 415/93, 415/97, 415/101, 415/102, 415/103, 415/120, 415/228, 415/900, 416/223 B, 416/189
• US Class Current: 417/423.1
• CPC Class Codes: F04D 13/064 Details of the magnetic circuit
• CPC Class Codes: F04D 13/0646 the hollow pump or motor shaft being the conduit for the working fluid
• CPC Class Codes: F04D 29/048 magnetic; electromagnetic
• CPC Class Codes: F04D 29/186 Shaftless rotors F04D13/024 takes precedence

Abstract

An integrated centrifugal pump and motor is provided by an impeller disk which contains permanent magnets and functions as the rotor for a brushless DC motor. The rotor is supported by non-contacting radial bearings and is hydrodynamically balanced against any axial thrust so that there is no contact between rotating and stationary elements during operation. Since the impeller disk is also the motor rotor, there is no need for a shaft, in the ordinary sense, which would penetrate the case and, thus, require seals. The resulting pump is compact and can be operated electronically at variable speeds.

Claims

1. A centrifugal pump comprising:

a housing having an internal chamber with inlet and discharge ports;

an impeller supported in said chamber for rotation about an axis, the impeller having a hub section having an axis about which it may rotate to pump a working fluid, the impeller having a central opening;

first and second disk shaped shrouds supported from said tub section, at least one of said shrouds containing permanent magnets; and

a plurality of pumping channels defined by a plurality of impeller blades projecting outwardly from the hub section in a common plane between said first and second shrouds so as to rotate in a common plane normal to said axis;

a motor stator coil for rotatably driving said impeller, the stator coil being disposed adjacent said shrouds so as to form a gap between the stator coil and the shroud for receiving a small quantity of pumped working fluid, the stator coil further having a central opening therein, the working fluid passing through the stator coil central opening and through the impeller central opening;

a means for axial hydrodynamic balancing of said impeller, the means comprising a ring disposed in said gap for restricting the flow of the small quantity of pumped working fluid;

a means for inducing flow of a working fluid toward the pumping channels from opposite directions, the means for inducing flow of a working fluid to the pumping channels comprising an opening between the hub section and each shroud and an inducer in the opening, the inducer comprising a pumping member which is separate from the impeller; and

a recirculation passage adjacent each inducer.

2. A centrifugal pump comprising:

a housing having an internal chamber with inlet and discharge ports;

an impeller supported in said chamber for rotation about an axis, the impeller having a hub section;

at least one disk shaped shroud containing permanent magnets;

a plurality of pumping channels defined by a plurality of impeller blades projecting outwardly from the hub section and fixed to a face of the shroud; and

means for supplying fluid to the pumping channels, said means comprising at least one opening between the hub section and the shroud; and

one or more inducers in said opening, said inducers comprising pumping members which are separate from the impeller blades; and

a recirculation passage adjacent each inducer.

3. A centrifugal pump comprising:

a housing having an internal chamber connecting inlet and discharge ports;

a disk shaped impeller having permanent magnets disposed therein, said impeller being supported within said chamber for rotation about an axis to pump a working fluid;

a motor stator coil for rotatably driving said impeller, said stator coil being disposed at a side of said impeller so as to form a gap between the stator coil and the impeller for receiving a small quantity of pumped working fluid; and

a means for axial hydrodynamic balancing of said impeller, the means comprising a ring disposed in said gap for restricting flow of the small quantity of pumped working fluid therethrough.

4. A centrifugal pump as claimed in claim 3 and further comprising a second motor stator coil and a second ring, said impeller being disposed between the first and second motor stator coils and said second ring being disposed in a second gap between said second motor stator coil and said impeller for restricting the flow of pumped working fluid therethrough.