| 摘要 |
<p>A centrifugal blood pump having a pumping chamber provided with an axial inlet (12) and a circumferential outlet (14) and provided with a rotatable impeller (16) having a plurality of radially extending blood propelling vanes (30,32). The vanes (30,32) are configured to each have a blade angle which varies monotonically toward the periphery of the chamber. The pumping chamber (16) is delimited by an impeller housing (2) provided with an opening through which the impeller shaft (20) extends into the chamber, the opening having an outline which conforms closely to the outline of the shaft (20), and the pump further includes a bearing housing (8) secured to the impeller housing (2) and delimiting a bearing chamber into which the shaft extends; bearings (22) disposed in the bearing chamber and rotatably supporting the shaft (20); and a seal (36) located in the bearing chamber adjacent the opening and surrounding the shaft (20) to form a fluid seal between the blood pumping chamber (6) and the bearing chamber. The impeller (16) is driven by a plurality of magnetizable plates (28) secured to the impeller and spaced apart about the longitudinal axis, and a rotatable magnetic drive assembly disposed outside of the impeller housing and mounted for rotation about the longitudinal axis, the drive assembly producing a magnetic field which passes through each plate (28) for attracting the plates (28) to the drive assembly and rotating the impeller (16) with the drive assembly. <IMAGE></p> |
