Hoshi Hideo, Katakoa Kiroyuki, Ohuchi Katsuhiro, Asama Jun-ichi, Shinshi Tadahiko, Shimokohbe Akira, Takatani Setsuo
Department of Artificial Organs, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan.
ASAIO J. 2005 Jan-Feb;51(1):60-4. doi: 10.1097/01.mat.0000151148.72891.55.
A new magnetic bearing has been designed to achieve a low electronic power requirement and high stiffness. The magnetic bearing consists of 1) radial passive forces between the permanent magnet ring mounted inside the impeller rotor and the electromagnet core materials in the pump casing and 2) radial active forces generated by the electromagnets using the two gap sensor signals. The magnetic bearing was assembled into a centrifugal rotary blood pump (CRBP) driven with a radial, magnetic coupled driver. The impeller vane shape was designed based upon the computational fluid dynamic simulation. The diameter and height of the CRBP were 75 mm and 50 mm, respectively. The magnetic bearing system required the power of 1.0-1.4 W. The radial impeller movement was controlled to within +/- 10 microm. High stiffness in the noncontrolled axes, Z, phi, and theta, was obtained by the passive magnetic forces. The pump flow of 5 L/min against 100 mm Hg head pressure was obtained at 1,800 rpm with the electrical to hydraulic efficiency being greater than 15%. The Normalized Index of Hemolysis (NIH) of the magnetic bearing CRBP was one fifth of the BioPump BP-80 and one half of the NIKKISO HPM-15 after 4 hours. The newly designed magnetic bearing with two degrees of freedom control in combination with optimized impeller vane was successful in achieving an excellent hemolytic performance in comparison with the clinical centrifugal blood pumps.
一种新型磁轴承已被设计出来，以实现低电力需求和高刚度。该磁轴承由两部分组成：1）安装在叶轮转子内部的永磁环与泵壳中的电磁铁铁芯材料之间的径向被动力；2）电磁铁利用两个间隙传感器信号产生的径向主动力。该磁轴承被组装到一个由径向磁耦合驱动器驱动的离心式旋转血泵（CRBP）中。叶轮叶片形状是基于计算流体动力学模拟设计的。CRBP的直径和高度分别为75毫米和50毫米。磁轴承系统所需功率为1.0 - 1.4瓦。径向叶轮运动被控制在±10微米以内。在非受控轴Z、φ和θ方向上，通过被动力获得了高刚度。在1800转/分钟时，该泵在100毫米汞柱的扬程压力下流量达到5升/分钟，电 - 液效率大于15%。经过4小时后，磁轴承CRBP的归一化溶血指数（NIH）是BioPump BP - 80的五分之一，是NIKKISO HPM - 15的二分之一。与临床离心血泵相比，新设计的具有两自由度控制并结合优化叶轮叶片的磁轴承成功实现了优异的溶血性能。
