植入型骨導式助聽器之模擬設計

Simulation of an implant bone conduction hearing aid

潘世尉(Shih-Wei Pan)

指導教授 ： 蔡正倫

中原大學/工學院/醫學工程研究所/碩士(2006年)

https://doi.org/10.6840/cycu200600683

摘要

此研究所敘述之骨導式助聽器是使用一電磁鐵來驅動一個植入定位於頭骨上的永久磁鐵，以產生音頻的振動。而驅動永久磁鐵之電磁力的大小則是由磁鐵所處位置之磁場梯度與其本身的導磁係數來決定。
此研究的目地是應用有限元素的數學方法，來模擬電磁驅動器所產生的磁場與磁力，以改善驅動器的設計。藉由改變磁粉芯形狀的幾何參數可以修改線圈前方特定距離處的磁場梯度。其中，磁粉芯內芯的直徑與線圈尺寸比例對產生磁力大小的影響最大。模擬結果顯示，相對於目前所使用的電磁驅動器，可以將體積與重量減少70%，並且同時提升5倍的磁力。
電磁驅動器的轉換效率會決定其耗電量，一個經過最佳化設計的驅動器可使用較少的電流來產生更大的磁力，並且無需犧牲體積與重無需犧牲體積與重量。

關鍵字

電磁驅動器 ； 骨導式助聽器 ； 有限元素分析法

並列摘要

The bone conduction hearing aid described in this study is a permanent magnet anchored on the skull and driven by an electromagnet to generate acoustic vibration. The electromagnetic force applies on a permanent magnet is determined by the local gradient of magnetic field and the permeability of magnet.
The purpose of this study is to improve the design of the actuator by applying finite element method to simulate the magnetic field and force generated by the actuator. The geometric parameters of ferrite core and coil were adjusted to modify the gradient of magnetic field at a specific distance from the coil. The center core diameter and the coil size are the most important factors that affect the efficiency of actuator. Simulation results also show that about five folds of force can be achieved while the volume and weight is reduced to 30%.
The efficiency of the actuator is crucial in determining its power consumption. An optimized design generates more force with less current and without sacrificing the size and weight.

並列關鍵字

electromagnet ； bone conduction hearing aid ； finite element method (FEM)

參考文獻

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