US 4,846,152 A · Single-stage axial flow blood pump

Abstract

A miniature high-speed intravascular blood pump is formed as a single stage with two rows of rotor blades and a single row of stator blades within a tubular housing. The rotor's first row produces a mixed centrifugal and axial flow, while the rotor's second row produces a purely axial flow. The blades of the second row are shaped so as to produce a uniform blood flow along the trailing edges of the blades. For this purpose, the bases of the outer trailing edges of the second row blades have a negative propulsion angle. The pump has a purge-sealed hydrostatic bearing which is spring-loaded for minimum gap. The pump is driven by a cable encased in a dual-lumen, fluid-filled cable sheath formed of a coextrusion of a soft, blood-compatible outer layer and a stiff, abrasion-resistant inner layer. The cable sheath serves both as a purge fluid supply for the bearing, and as a means for flushing abraded debris away from the pump.

Claims15

Dependent claims

An intravascular blood pump, comprising:

(a) a substantially cylindrical stator;
and
(b) a rotor having a hub and cooperating with said stator to pump blood axially through said pump, said stator and rotor defining an annular space therebetween;
(c) means including two rows of blades on said rotor, for maintaining a radially uniform forward velocity of said blood in said annular space at the trailing edge of said rotor blade means, one of said rows producing a mixed axial and centrifugal flow, and the other producing a substantially pure axial flow.

1 more element

Dependencies are inferred from the claim text.

Single-stage axial flow blood pump

Life of this patent

Single-stage axial flow blood pump

Life of this patent

Abstract

Claims15