磁悬浮自动注射器驱动模型设计

Design of maglev auto syringe actuator model

目的:针对有针自动注射器精度差、低速振动以及无针自动注射器适用性差、难调节等问题,设计一种磁悬浮自动注射器驱动模型。方法:该模型基于洛伦兹力驱动原理设计,由永磁体N/S、磁轭、线圈、活塞推杆、针筒、外壳、位置传感器、控制器和功率放大器等构成。利用2对永磁体形成正对的磁场,连同针筒构成定子,线圈连接注射器活塞推杆构成动子,线圈通电后产生洛伦兹力驱动活塞推杆完成注射工作。根据模型受力与运动方程推导驱动系统数学模型,利用ANSYS软件对模型磁场与电磁力进行有限元分析。结果:磁场仿真结果显示磁场均匀稳定,磁感应强度稳定在0.83 T;电磁力仿真结果显示,电磁驱动力可达39.33 N,可以满足注射要求。结论:磁悬浮自动注射器驱动模型结构简单,可实现程序化控制且系统线性度好,适合多种场合使用。

Objective To design a maglev auto syringe actuator model to improve the needle syringe in low accuracy and vibration and the neddleless auto syringe in adaptability and adjustment.Methods The model was designed based on the Lorentz force principle,which consisted of permanent magnets N/S,a magnetic yoke,a coil,a piston pusher,a syringe,a housing,a position sensor,a controller and a power amplifier.Two pairs of permanent magnets formed a positive magnetic field,then a stator was composed with the positive magnetic field and the syringe,and an actuator was shaped with the coil connected with the piston pusher.The coil was energized to generate Lorentz force to drive the piston actuator to complete injection.A mathematical model of the drive system was derived from the force and motion equations of the model,and finite element analysis of the magnetic field and electromagnetic force was carried out using ANSYS.Results The magnetic field simulation results showed that the magnetic field was uniform and stable,and the magnetic induction strength was stable at 0.83 T.The electromagnetic force simulation results showed that the electromagnetic drive force could reach 39.33 N,which met the requirements for injection.Conclusion The maglev auto syringe actuator model designed gains advantages in simple structure,programmable control and system linearity,and is suitable for a wide range of applications.