US 5,746,575 A · Blood pump as centrifugal pump

Abstract

In a pump housing (10), the blood pump comprises an impeller (13) with a flat plate (30) and blades (34) projecting therefrom. The impeller (13) is supported between balls (18,20) forming an axial sliding bearing. The front wall (35) and the back wall (14) of the pump housing extend substantially parallel to the plate (30) of the impeller (13). The height of the blades (34) linearly decreases with increasing radius so that the gap between the front wall (35) and the blades (34) increases outwards. Since the circumferential speed increases as well, the shearing rate remains constant. Between the plate (30) of the impeller and the back wall (14), a gap of constant width is provided, in which secondary flows are produced, thereby avoiding dead water zones.

Claims12

Dependent claims

A pump comprising a pump housing having

an axial inlet;
a tangential outlet;
a front wall;
a back wall;
an impeller rotatably supported in said pump housing, said impeller comprising
a plate having a back side arranged at a substantially constant distance from the back wall of said pump housing,
blades projecting from the plate and beyond the plate in a radially outward direction, said blades having a height that decreases in the radially outward direction;
wherein the front wall of said pump housing extends substantially parallel to the plate of said impeller and the back wall of said pump housing includes a circumferential sloping portion located beyond the plate and defining a transition to the tangential outlet.

5 more elements

Dependencies are inferred from the claim text.

Blood pump as centrifugal pump

Life of this patent

Blood pump as centrifugal pump

Life of this patent

Abstract

Claims12