可調頻式壓電片應用於醫療用PCA投藥幫浦之設計與效能分析

Design and Analysis of a Patient-Controlled Analgesia Micropump by Using the Frequency-modulated PZT Bimorph

吳家禕(Chia-Yi Wu)

指導教授 ： 馬小康

國立臺灣大學/工學院/機械工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.02959

摘要

本研究對制動元件壓電片的振幅放大機制作相關研究，由實驗中可以發現，在壓電片箝制端的力越大，會使得壓電片的共振頻率變大，透過此種設計可以使壓電片在30Hz到80Hz都可成為壓電片共振頻率，此時振幅放大，放大的倍率將近兩倍。同時利用此裝置，把調頻的壓電片作為PCA投藥幫浦之制動元件，達到放大流量的效果。除此之外，針對PCA投藥幫浦的幾何形狀和醫療規範限制，做相關的設計跟研究。首先利用CFD-RC軟體模擬並確定傳力圓柱的特性，了解單點施力的情況優於雙點施力，並利用實驗來做驗證，同時探討不同施力點的直徑大小與施力位置對性能的影響，而且使用醫療規範之薄膜，對不同的薄膜厚度做性能的分析，發現在薄膜厚度為0.24mm時有最佳的效果，流量最大為26ml/min，而流向的控制是透過單一閥件來控制，故對閥件的寬度、厚度、材料做相關性能分析實驗，最後對腔室大小做相關分析，腔室大小分別為10mm x 10mm x 3mm以及20mm x 10mm x 3mm。發現在腔室大小為20mm x 10mm x 3mm，圓柱半徑為2.5mm時最大流量為28ml/min，發生在施力位置為圓柱圓心距壓電片末端5mm，頻率為75Hz。

關鍵字

單邊擺動 ； 壓電元件 ； 流向元件 ； PCA投藥幫浦 ； 可調頻

並列摘要

In this study, an innovative one-side actuating Piezoelectric Transducer (PZT) micropump with an adjustable frequency modulator has been developed for a portable biomedical device. The PZT micropump which consists of a pump chamber and one passive check valve is used as a disposable Patient-Controlled Analgesia (PCA) pump. Because of the restriction of the micropump size, there is a component which transmits force from the PZT to the chamber. First, in order to simulate the performance of one-point mode and two-point mode, the software, CFD-RC, is used. The result shows that one-point mode has better performance. And the experiment result shows the same tendency. Furthermore, the influence of different position and different diameter of the transmitting component has been studied. Due to the standardization of the medicine restriction, the membrane is chosen as silica gel. And different thickness of the membrane has been studied. The result shows that the maximum flow rate is 26ml/min, which happens at the thickness of 0.24mm. The flow direction of the micropump is determined by the valve, so the influence of thickness and the diameter of the valve have been researched. The chamber size is also an important parameter affecting the performance of the micropump, two size, 10mm × 10mm × 3mm and 20mm × 10mm × 3mm, have been studied. And the maximum flow rate is 28ml/min, when the chamber size is 20mm × 10mm × 3mm, and the operating frequency is 75Hz.

並列關鍵字

One-side actuation ； Piezoelectric device ； Flow-direction ； PCA micropump ； frequency modulation

參考文獻

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