Blood pump

• US 20030039544A1
• Filed: 07/15/2002
• Published: 02/27/2003
• Est. Priority Date: 08/10/2001
• Status: Active Grant

• Current Assignee: Sun Medical Technology Research Corporation (Misuzu & Sun Medical Holdings Co., Ltd.)
• Original Assignee: Sun Medical Technology Research Corporation (Misuzu & Sun Medical Holdings Co., Ltd.)
• Inventors: Yamazaki, Kenji
• Granted Patent: US 6,908,280 B2
• Time in Patent Office: Days
• US Class Current: 415/206
• CPC Class Codes: A61M 60/148 in line with a blood vessel using resection or like techniques, e.g. permanent endovascular heart assist devices
• CPC Class Codes: 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
• CPC Class Codes: A61M 60/232 Centrifugal pumps
• CPC Class Codes: A61M 60/804 Impellers
• CPC Class Codes: A61M 60/827 Sealings between moving parts
• CPC Class Codes: A61M 60/829 having a purge fluid supply
• CPC Class Codes: F04D 13/0606 Canned motor pumps
• CPC Class Codes: F04D 29/106 especially adapted for liquid pumps
• CPC Class Codes: F04D 29/242 Geometry, shape
• CPC Class Codes: F04D 29/426 especially adapted for liquid pumps
• CPC Class Codes: Y10S 415/90 Rotary blood pump

Abstract

The blood pump of the present invention comprises:

a first casing (1), its rim forming an opening; a second casing (2) having an inlet opening at the top and an outlet opening at an arbitrary position;

a pump base part (5) attached to the first and second casings to partition them, its one side facing and covering the rim of the first casing, and the other side facing the base rim of the second casing;

a drive part (7) housed inside the first casing driving a rotation shaft with a boss on the tip going roughly through the middle of the pump base part; a plurality of impellers (11) extending in radial direction from the outer periphery of the boss; and

a pump part (3) constituted by the concurrence of the plurality of impellers and the second casing,

wherein the impellers'"'"' boss attachment parts are shifted forward towards the inlet opening.

wherein one part is cut out in each of the plurality of impellers'"'"' surfaces to form a window opening part (13).

As a result, the blood pump of the present invention ensures smooth blood flow and therefore allows to effectively prevent the development of thrombi.

Claims

1. A blood pump, comprising:

a first casing, its rim forming an opening;

a second casing having an inlet opening at the top and an outlet opening at an arbitrary position;

a pump base part attached to the first and second casings to partition them, its one side facing and covering the rim of the first casing, and the other side facing the base rim of the second casing;

a drive part housed inside the first casing driving a rotation shaft with a boss on the tip going roughly through the middle of the pump base part;

a plurality of impellers extending in radial direction from the outer periphery of the boss; and

a pump part constituted by the concurrence of the plurality of impellers and the second casing,

wherein the impellers'"'"' boss attachment parts are shifted forward towards the inlet opening.

2. A blood pump according to claim 1, wherein one part is cut out in each of the plurality of impellers'"'"' surfaces to form a window opening part.

3. A blood pump according to claim 2, wherein a mechanical seal is provided at the base rim side of the boss of about the same diameter as the boss base rim, the window opening part is cut out starting from the position where the impellers are supported by the boss and continuing so as to avoid the rotating part of the mechanical seal, with the end of the cut out line being formed to correspond to the position of the friction surface of the mechanical seal.

4. A blood pump according to claim 1, wherein the inner wall of the second casing is tapered, continuously increasing in width from the inlet opening towards the base rim, and formed to draw as close as possible to the outer outline of the impellers, the boss and impellers being surrounded by the inner wall and protruding towards the inlet opening.

5. A blood pump according to claim 4, wherein the clearance between the second casing'"'"'s inner wall and the impellers'"'"' outer outline ranges between 0.1 mm and 3.0 mm.

6. A blood pump according to claim 1, wherein each impeller of the plurality of impellers features an inducer on the inlet opening side of the impeller, the inducer being layed-out to be inclined at a prescribed angle against each impeller.

7. A blood pump according to claim 1, wherein the pump base part features a convex part protruding towards the second casing, the convex part'"'"'s flank being formed to slope gently so as to draw as close as possible to the inner outline of the impellers.

8. A blood pump according to claim 7, wherein the clearance between the pump base part and the inner outline of the impellers ranges between 0.05 mm and 3.0 mm.

9. A blood pump according to claim 1, wherein

one part is cut out in each of the plurality of impellers'"'"' surfaces to form a window opening part;

the inner wall of the second casing is tapered, continuously increasing in width from the inlet opening towards the base rim, and is formed to draw as close as possible to the outer outline of the impellers, the boss and impellers being surrounded by the inner wall and protruding towards the inlet opening;

each impeller of the plurality of impellers features an inducer on the inlet opening side of the impeller, the inducer being layed-out to be inclined at a prescribed angle against each impeller; and

the pump base part features a convex part protruding towards the second casing, the convex part'"'"'s flank being formed to slope gently so as to draw as close as possible to the inner outline of the impellers.

10. A blood pump, comprising:

a first casing, its rim forming an opening;

a second casing having an inlet opening at the top and an outlet opening at an arbitrary position;

a pump base part attached to the first and second casings to partition them, its one side facing and covering the rim of the first casing, and the other side facing the base rim of the second casing;

a drive part housed inside the first casing driving a rotation shaft with a boss on the tip going roughly through the middle of the pump base part;

a plurality of impellers extending in radial direction from the outer periphery of the boss; and

a pump part constituted by the concurrence of the plurality of impellers and the second casing,

wherein one part is cut out in each of the plurality of impellers'"'"' surfaces to form a window opening part.

11. A blood pump according to claim 10, wherein a mechanical seal is provided at the base rim side of the boss of about the same diameter as the boss base rim, the window opening part is cut out starting from the position where the impellers are supported by the boss and continuing so as to avoid the rotating part of the mechanical seal, with the end of the cut out line being formed to correspond to the position of the friction surface of the mechanical seal.

12. A blood pump, comprising:

a first casing, its rim forming an opening;

a second casing having an inlet opening at the top and an outlet opening at an arbitrary position;

a pump base part attached to the first and second casings to partition them, its one side facing and covering the rim of the first casing, and the other side facing the base rim of the second casing;

a drive part housed inside the first casing driving a rotation shaft with a boss on the tip going roughly through the middle of the pump base part;

a plurality of impellers extending in radial direction from the outer periphery of the boss; and

a pump part constituted by the concurrence of the plurality of impellers and the second casing,

wherein the inner wall of the second casing is tapered, continuously increasing in width from the inlet opening towards the base rim, and formed to draw as close as possible to the outer outline of the impellers, the boss and impellers being surrounded by the inner wall and protruding towards the inlet opening.

13. A blood pump according to claim 12, wherein the clearance between the second casing'"'"'s inner wall and the impellers'"'"' outer outline ranges between 0.1 mm and 3.0 mm.

14. A blood pump, comprising:

a first casing, its rim forming an opening;

a second casing having an inlet opening at the top and an outlet opening at an arbitrary position;

a pump base part attached to the first and second casings to partition them, its one side facing and covering the rim of the first casing, and the other side facing the base rim of the second casing;

a drive part housed inside the first casing driving a rotation shaft with a boss on the tip going roughly through the middle of the pump base part;

a plurality of impellers extending in radial direction from the outer periphery of the boss; and

a pump part constituted by the concurrence of the plurality of impellers and the second casing,

wherein each impeller of the plurality of impellers features an inducer on the inlet opening side of the impeller, the inducer being layed-out to be inclined at a prescribed angle against each impeller.

15. A blood pump according to claim 14, wherein the inducers are shifted forward towards the inlet opening.

16. A blood pump, comprising:

a first casing, its rim forming an opening;

a second casing having an inlet opening at the top and an outlet opening at an arbitrary position;

a pump base part attached to the first and second casings to partition them, its one side facing and covering the rim of the first casing, and the other side facing the base rim of the second casing;

a drive part housed inside the first casing driving a rotation shaft with a boss on the tip going roughly through the middle of the pump base part;

a plurality of impellers extending in radial direction from the outer periphery of the boss; and

a pump part constituted by the concurrence of the plurality of impellers and the second casing,

wherein the pump base part features a convex part protruding towards the second casing, the convex part'"'"'s flank being formed to slope gently so as to draw as close as possible to the inner outline of the impellers.

17. A blood pump according to claim 16, wherein the clearance between the pump base part and the inner outline of the impellers ranges between 0.05 mm and 3.0 mm.