Masuzawa T, Kita T, Okada Y
Department of Mechanical Engineering, Faculty of Engineering, Ibaraki University, Ibaraki, Japan.
Artif Organs. 2001 May;25(5):395-9. doi: 10.1046/j.1525-1594.2001.025005395.x.
A magnetically suspended centrifugal blood pump has been developed with a self-bearing motor for long-term ventricular assist systems. The rotor of the self-bearing motor is not only actively suspended in the radial direction, but also is rotated by an electromagnetic field. The pump has a long lifetime because there are no mechanical parts such as seals and motor bearings. An outer rotor mechanism was adopted for the self-bearing motor. The stator was constructed in the central space of the motor. The rotor shaped thin ring was set at the circumferential space of the stator. Six vanes were extended from the upper surface of the rotor toward the center of the pump to construct an open-type impeller. The outer diameter and the height of the impeller are 63 mm and 34 mm, respectively. The magnetic bearing method and the servomotor mechanism were adopted to levitate and rotate the rotor. Radial movements of the rotor and rotation are controlled actively by using electromagnets in the stator. Axial movement and tilt of the rotor are restricted by passive stability to simplify the control. The radial gap between the rotor and the stator is 1 mm. A closed-loop circuit filled with water was used to examine basic performance of the pump. Maximum flow rate and pressure head were 8 L/min and 200 mm Hg, respectively. Maximum amplitude of radial displacement of the impeller was 0.15 mm. The impeller could be suspended completely without touching the casing wall during the entire pumping process. Power consumption of the pump was only 9.5 W to produce a flow rate of 5 L/min against a pressure head of 100 mm Hg. We conclude that the pump has sufficient performance for the implantable ventricular assist system.
一种带有自支承电机的磁悬浮离心血泵已被开发出来，用于长期心室辅助系统。自支承电机的转子不仅在径向被主动悬浮，而且由电磁场驱动旋转。由于没有诸如密封件和电机轴承等机械部件，该泵具有较长的使用寿命。自支承电机采用了外转子机构。定子构建在电机的中心空间内。转子形状的薄环设置在定子的圆周空间。六个叶片从转子的上表面向泵的中心延伸，以构成一个开式叶轮。叶轮的外径和高度分别为63毫米和34毫米。采用磁轴承方法和伺服电机机构来悬浮和旋转转子。利用定子中的电磁铁主动控制转子的径向运动和旋转。转子的轴向运动和倾斜通过被动稳定性来限制，以简化控制。转子与定子之间的径向间隙为1毫米。使用充满水的闭环回路来测试泵的基本性能。最大流量和压头分别为8升/分钟和200毫米汞柱。叶轮径向位移的最大幅度为0.15毫米。在整个泵送过程中，叶轮可以完全悬浮而不接触泵壳壁。该泵在产生5升/分钟的流量、对抗100毫米汞柱的压头时，功耗仅为9.5瓦。我们得出结论，该泵对于可植入心室辅助系统具有足够的性能。
