# US 8,540,477 B2 · Rotary pump with thrust bearings > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,540,477 B2 - Document ID: US8540477B2 - Status: Granted - Kind: B2 - Application number: 13/198,315 - Filed: 2011-08-04 - Published: 2012-03-15 - Granted: 2013-09-24 - Earliest claimed: 2006-01-13 - Assignees: HeartWare, Inc. - Applicants: Jeffrey A. LaRose; Charles R. Shambaugh - Inventors: Jeffrey A. LaRose; Charles R. Shambaugh - Web page: https://patentgrep.com/patent/US8540477B2 ## CPC - F04D 13/066: {Floating-units} - A61M 60/148: in line with a blood vessel using resection or like techniques, e.g. permanent endovascular heart assist devices - A61M 60/178: drawing blood from a ventricle and returning the blood to the arterial system via a cannula external to the ventricle, e.g. left or right ventricular assist devices - A61M 60/232: Centrifugal pumps - A61M 60/422: the force acting on the blood contacting member being electromagnetic, e.g. using canned motor pumps - A61M 60/592: Communication of patient or blood pump data to distant operators for treatment purposes - A61M 60/82: Magnetic bearings - A61M 60/824: Hydrodynamic or fluid film bearings - A61M 60/871: Energy supply devices; Converters therefor - F04D 7/04: the fluids being viscous or non-homogenous - F04D 13/0633: {Details of the bearings} - F04D 13/0666: {the motor being of the plane gap type} - F04D 29/0413: {hydrostatic; hydrodynamic thrust bearings} - F04D 29/0473: {for radial pumps} - F04D 29/048: magnetic; electromagnetic - F04D 29/22: specially for centrifugal pumps - F04D 29/2255: {flow-channels with a special cross-section contour, e.g. ejecting, throttling or diffusing effect} - Y10S 415/90: Rotary blood pump - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract A rotary blood pump includes a casing defining a pumping chamber. The pumping chamber has a blood inlet and a tangential blood outlet. One or more motor stators are provided outside of the pumping chamber. A rotatable impeller is within the pumping chamber and is adapted to cause blood entering the pumping chamber to move to the blood outlet. The impeller has one or more magnetic regions. The impeller is radially constrained in rotation by magnetic coupling to one or more motor stators and is axially constrained in rotation by one or more hydrodynamic thrust bearing surfaces on the impeller. ## Claims ### Claim 1 A rotary pump comprising: a pumping chamber; a rotor within said pumping chamber having a plurality of axially raised bodies spaced apart to define fluid flow paths therebetween; each of said raised bodies having an upper surface area along which a first inclined region extends from a leading edge to a trailing boundary region, a gap between each first inclined region and an axially upper interior wall of said pumping chamber decreasing towards said trailing boundary region to increase axial fluid pressure in said gap when said rotor is rotating; said upper surface area of each of said raised bodies having a second inclined region extending from said trailing boundary region to a trailing edge of said second inclined region, a gap between each of said second inclined regions and said axially upper interior wall increasing towards said trailing edge to decrease axial fluid pressure in said gap when said rotor is rotating; inner and outer boundaries of each first inclined region being defined by respective inner and outer shrouds, an interior side of each inner shroud defining a downwardly tapered and concavely shaped inwardly facing surface area coextensive with said inner shroud and descending toward the center of the rotor. ### Claim 2 (depends on 1) The rotary pump of claim 1 in which each leading edge has a radius of curvature of no more than 0.010 inches. ### Claim 3 (depends on 2) The rotary pump of claim 2 in which each leading edge has a radius of curvature of approximately 0.005 inches. ### Claim 4 (depends on 1) The rotary pump of claim 1 in which said leading and trailing edges are approximately the same length. ### Claim 5 (depends on 1) The rotary pump of claim 1 in which said rotor comprises four of said raised sectors. ### Claim 6 (depends on 1) The rotary pump of claim 1 in which each of said shrouds has a top surface that is substantially flat and higher than said leading edge by approximately 0.230 inches. ### Claim 7 (depends on 6) The rotary pump of claim 6 in which said top surface of each of said shrouds is approximately 0.020 inches wide. ### Claim 8 (depends on 1) The rotary pump of claim 1 in which a radially outer surface of each of said outer shrouds defines a portion of the periphery of said rotor. ### Claim 9 (depends on 1) The rotary pump of claim 1 in which said pumping chamber is formed from a ceramic material. ### Claim 10 (depends on 1) The rotary pump of claim 1 in which said axially upper interior wall comprises a ceramic disk. ### Claim 11 (depends on 1) The rotary pump of claim 1 in which said pumping chamber comprises an axially lower interior wall comprising a ceramic disk. ### Claim 12 (depends on 1) The rotary pump of claim 1 in which said leading and trailing edges are of unequal axial height. ### Claim 13 (depends on 12) The rotary pump of claim 12 in which said leading edges are axially higher than said trailing edges.