短期辅助用直流电磁驱动搏动式血泵设计与测试

The Design and Test of Pulsating Blood Pump Driven by Direct-Current Electromagnetism for Temporary Assistance

设计一种直流电磁驱动搏动式血泵并测试样机性能指标。首先,提出一种通过直流螺线管使永磁体进行往复直线运动的驱动方法,并通过螺线管内部磁场的数值模拟设计内部磁场趋于匀强磁场的补偿螺线管结构,结合两者设计直流电磁驱动搏动式血泵。然后,通过制作样机并搭建加速度实验台,测量接入不同直流电流时血泵样机可提供的磁力驱动力,并验证通电螺线管发热问题。最后,搭建流量实验台,在前、后负荷范围分别为5~30和50~80 mm Hg的情况下,测量血泵样机的流量性能指标。血泵样机提供的磁力驱动力与电流呈正相关线性关系,并且在接入2.7 A的电流时,其数值大小即可满足驱动要求;在接入的直流电流为2.7 A且血泵驱动频率为80次·min-1时,一方面通电螺线管与血液接触的内表面温度上升1℃后平稳在27℃,另一方面除了前、后负荷压差达到70 mm Hg及以上,血泵样机流量均大于3.0 L·min-1。该直流电磁驱动血泵满足离体器官灌注和体外循环短期辅助的临床要求,且对体外循环血泵的发展具有重要意义。

The aims of this work are to design a pulsating blood pump driven by direct-current electromagnetism and to evaluate the performance indices of prototype. First of all,the pulsating blood pump driven by directcurrent electromagnetism was designed with both the drive method of the reciprocating rectilinear motion of a magnet implemented by utilizing solenoids with direct current and the structure of compensation solenoid within uniform magnetic field which was designed through numerical simulation. Next,the value of magnetic driving force created by the blood pump was measured with the prototype and the acceleration test bed when the different current was applied. After that,none heating problem of energized solenoids was detected through calculation and experiment. Finally,the flow performance index of prototype was measured in the conditions that the ranges of preload or afterload were 5-30 mm Hg and 50-80 mm Hg respectively through the flow test bed. The magnetic driving force created by the prototype possessed the positive linear relation to the current and accorded with the design requirement when the current was 2. 7 A. When the current was 2. 7 A and the driving frequency was 80 per min,the temperature on the internal surface of energized solenoids contacting with the blood was raised 1 ℃ and stabilized at 27 ℃,the flow of prototype was over 3. 0 L·min-1 except that the gap between preload and afterload was more than 70 mm Hg. The pulsating blood pump driven by direct-current electromagnetism reached the clinical requirement of the perfusion of organs isolated and the temporary assistance of extracorporeal circulation,and the design was of significance to the development of extracorporeal circulation blood pump.