Patent ID: 9366261
Filing Date: 2016-06-14
CPC Classification: A61M,F04D

Claim Text:
1. A centrifugal pump device, comprising: a housing including a first and a second chamber divided by a barrier wall; an impeller rotatably provided along the barrier wall in the first chamber that sends a liquid to an outflow port by centrifugal force during rotation of the impeller; and a drive portion provided in the second chamber that rotatably drives the impeller with the barrier wall therebetween; and comprising a first magnetic body provided on a first face of the impeller, a second magnetic body provided on an inner wall of the first chamber opposing the first face of the impeller that attracts the first magnetic body, wherein the second magnetic body has a greater attractive force at a first portion of the housing proximate to the outflow port than at a second portion of the housing distal to the outflow port, and a plurality of first permanent magnets provided on a second face of the impeller arranged along a circle such that adjacent magnetic poles are mutually different; wherein the drive portion includes a plurality of third magnetic bodies provided opposing the plurality of first permanent magnets, and a plurality of coils provided corresponding to each of the plurality of third magnetic bodies wound around each corresponding third magnetic body to generate a rotating magnetic field; a first attractive force between the first and the second magnetic bodies and a second attractive force between the plurality of first permanent magnets and the plurality of third magnetic bodies balance in a substantial center of a range of movement of the impeller in the first chamber during rotation of the impeller; and a first hydrodynamic groove is formed on the first face of the impeller or on the inner wall of the first chamber facing thereto, and a second hydrodynamic groove is formed on the second face of the impeller or on the barrier wall facing thereto.