Centrifugal pump

Patent metadata

Field	Value
Publication number	US-2016208804-A1
Application number	US-201615082291-A
Country	US
Kind code	A1
Filing date	Mar 28, 2016
Priority date	Dec 27, 2013
Publication date	Jul 21, 2016
Grant date	—

Abstract

A centrifugal pump ( 10 ) includes a housing ( 26 ), an impeller ( 28 ) that is rotatably disposed inside the housing ( 26 ), a shaft ( 62 ) that has spherical surface-shaped shaft ends ( 66 ) at both ends in an axial direction, and bearings ( 70 ) that have spherical surface-shaped bearing surfaces ( 73 ) respectively and pivotally supporting the shaft ends ( 66 ). In at least one of the bearings ( 70 ) disposed on both sides of the shaft ( 62 ) in the axial direction, a ratio of a radius of curvature of the shaft end ( 66 ) with respect to a radius of curvature of the bearing surface ( 73 ) of the bearing ( 70 ) is equal to or less than 85%.

First claim

What is claimed is:

1 . A centrifugal pump comprising:
a housing; an impeller rotatably disposed inside the housing; a shaft fixed to the impeller at a central rotational axis and having spherically-shaped axial ends each with a respective radius of curvature; and first and second bearings having spherically-shaped bearing surfaces, respectively, each with a respective radius of curvature and pivotally supporting a respective shaft axial end; wherein a ratio of the radius of curvature of one of the shaft ends with respect to the radius of curvature of the respective bearing surface is equal to or less than 85%.

2 . The centrifugal pump according to claim 1 ,
wherein the radius of curvature of at least one of the shaft ends ranges from 1.25 mm to 1.5 mm, and the radius of curvature of the respective bearing surface ranges from 1.5 mm to 2.5 mm.

3 . The centrifugal pump according to claim 1 ,
wherein the radius of curvature of at least one of the shaft ends is 1.5 mm, and the radius of curvature of the respective bearing is 2.0 mm.

4 . The centrifugal pump according to claim 1 ,
wherein a bearing preload with respect to the shaft is in a range from 30 N to 60 N.

5 . The centrifugal pump according to claim 1 ,
wherein an outer diameter of the impeller is equal to or greater than 70 mm, and wherein a maximum rotational frequency of the impeller is equal to or less than 3,000 rpm.

Assignees

• Terumo Corp

Inventors

• Kumano Koko

Classifications

• A61M1/3666

  Cardiac or cardiopulmonary bypass, e.g. heart-lung machines · CPC title

• F04D1/00

  Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps (adapted for pumping specific fluids F04D7/00; priming or boosting F04D9/00) · CPC title

• F04D29/041

  Axial thrust balancing · CPC title

• F04D13/026 Primary

  Details of the bearings · CPC title

• A61M1/1013

  Human Necessities · mapped topic