BLOOD PUMP WITH MICROMOTOR

• US 20100041939A1
• Filed: 03/14/2008
• Published: 02/18/2010
• Est. Priority Date: 03/24/2007
• Status: Active Grant

• Current Assignee: ABIOMED Europe GmbH (Johnson & Johnson)
• Original Assignee: ABIOMED Europe GmbH (Johnson & Johnson)
• Inventors: Siess, Thorsten
• Granted Patent: US 10,808,704 B2
• Time in Patent Office: Days
• US Class Current: 600/16
• CPC Class Codes: A61M 60/13 by means of a catheter allowing explantation, e.g. catheter pumps temporarily introduced via the vascular system
• 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 60/211 using a jet, venturi or entrainment effect for pumping the blood
• CPC Class Codes: A61M 60/221 the blood flow through the rotating member having both radial and axial components, e.g. mixed flow pumps
• CPC Class Codes: A61M 60/237 the blood flow through the rotating member having mainly axial components, e.g. axial flow pumps
• CPC Class Codes: A61M 60/416 transmitted directly by the motor rotor drive shaft
• CPC Class Codes: A61M 60/422 the force acting on the blood contacting member being electromagnetic, e.g. using canned motor pumps
• CPC Class Codes: A61M 60/577 High-frequency driving
• CPC Class Codes: A61M 60/825 Contact bearings, e.g. ball-and-cup or pivot bearings
• CPC Class Codes: F04D 13/0626 Details of the can
• CPC Class Codes: F04D 13/064 Details of the magnetic circuit
• CPC Class Codes: F04D 3/00 Axial-flow pumps priming or boosting F04D9/00

Abstract

The invention relates to a micromotor (10), the stator of which contains a back iron jacket (18). Said back iron jacket consists of a continuous unslotted sleeve consisting of a metal alloy that contains ferritic iron as the main constituent, up to 30% chromium and preferably aluminium and yttrium oxide. Electric conductivity is reduced by the oxidation of the aluminium. The yttrium oxide performs the same function. The reduced electric conductivity suppresses eddy currents to a great extent. The back iron jacket (18) has a high magnetic conductivity with a small wall thickness, thus increasing the electrical output for a motor with a small diameter.

Claims

1. A blood pump with micromotor (10), provided for intracorporeal use, said blood pump comprising a stator (15) accommodating a shell (17) containing an exciter coil (24), and accommodating a magnetic-reflux jacket (18) made of magnetically conductive material and surrounding said shell (17),

characterized in

that said magnetic-reflux jacket (18) consists of a one-pieced unslotted shell made of a ferritic material containing iron as the main component and up to 30% chromium.

2. The blood pump according to claim 1, characterized in that the material of the magnetic-reflux jacket (18) contains up to 8% aluminum.

3. The blood pump according to claim 1, characterized in that the material of the magnetic-reflux jacket (18) contains up to 2% yttrium oxide.

4. The blood pump according to claim 1, characterized in that the material of the magnetic-reflux jacket (18) contains maximally 0.2% copper.

5. The blood pump according to claim 1, characterized in that the material of the magnetic-reflux jacket (18) contains, apart from iron, the following components:

chromium 18.50%-21.50% aluminum 3.75%-5.75% titanium 0.20%-0.60% carbon 0.10% max. yttrium oxide 0.30%-0.70% copper 0.15% max. manganese 0.30% max. cobalt 0.30% max. nickel 0.50% max. phosphorus 0.02% max.

6. The blood pump according to claim 1, wherein the outer diameter of the magnetic-reflux jacket does not exceed 4.6 mm and the inner diameter is at least 3.3 mm.

7. The blood pump according to claim 1, wherein windows are provided on the proximal end of the magnetic-reflux jacket.

8. The blood pump according to claim 1, wherein the magnetic-reflux jacket is connected to the pump housing by a welding seam.