Shin Dong Ho, Seong Ki Woong, Puria Sunil, Lee Kyu-Yup, Cho Jin-Ho
School of Electronics Engineering, College of IT Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu, Republic of Korea.
Department of Biomedical Engineering, Kyungpook National University Hospital, 130 Dongdeok-ro, Jung-gu, Daegu, Republic of Korea.
Hear Res. 2016 Nov;341:144-154. doi: 10.1016/j.heares.2016.08.013. Epub 2016 Sep 2.
A number of methods to drive the round window (RW) using a floating mass transducer (FMT) have been reported. This method has attracted attention because the FMT is relatively easy to implant in the RW niche. However, the use of an FMT to drive the RW has been proven to produce low outputs at frequencies below approximately 1 kHz. In this study, a new tri-coil bellows-type transducer (TCBT), which has excellent low frequency output and is easy to implant, is proposed. To design the frequency characteristics of the TCBT, mechanical and electrical simulations were performed, and then a comparative analysis was conducted between a floating mass type transducer (like the FMT) and a fixed type transducer (like the TCBT). The features of the proposed TCBT are as follows. First, the TCBT's housing is fixed to the RW niche so that it does not vibrate. Second, the internal end of a tiny bellows is connected to a vibrating three-pole permanent magnet located within three field coils. Finally, the rim of the bellows bottom is attached to the end of the housing that hermetically encloses the three field coils. In this design, the only vibrating element is the bellows itself, which efficiently drives the RW membrane. To evaluate the characteristics of this newly developed TCBT, the transducer was installed in the RW niche of temporal bones and the velocity of the stapes was measured using a laser Doppler vibrometer. The experimental results indicate that the TCBT can produce 100, 111, and 129 dB SPL equivalent pressure outputs at below 1 kHz, 1-3 kHz, and above 3 kHz, respectively. Thus, the TCBT with one side coupled to the RW via a bellows will be easy to implant and offer better performance than an FMT.
已经报道了多种使用浮动质量换能器（FMT）驱动圆窗（RW）的方法。这种方法受到关注是因为FMT相对容易植入圆窗龛。然而，已证明使用FMT驱动RW在频率低于约1kHz时输出较低。在本研究中，提出了一种新型的三线圈波纹管式换能器（TCBT），它具有出色的低频输出且易于植入。为了设计TCBT的频率特性，进行了机械和电气模拟，然后对浮动质量型换能器（如FMT）和固定型换能器（如TCBT）进行了对比分析。所提出的TCBT的特点如下。首先，TCBT的外壳固定在圆窗龛上，使其不振动。其次，一个微小波纹管的内端连接到位于三个励磁线圈内的振动三极永磁体。最后，波纹管底部的边缘连接到密封包围三个励磁线圈的外壳端部。在这种设计中，唯一的振动元件是波纹管本身，它能有效地驱动RW膜。为了评估这种新开发的TCBT的特性，将该换能器安装在颞骨的圆窗龛中，并使用激光多普勒振动计测量镫骨的速度。实验结果表明，TCBT在低于1kHz、1 - 3kHz和高于3kHz时分别可产生100、111和129dB SPL的等效压力输出。因此，一侧通过波纹管与RW耦合的TCBT将易于植入，并且比FMT具有更好的性能。
