为了提高超磁致伸缩换能器的作动行程, 以获得足够大的发音强度, 并使之满足发音装置体积小、装配零件少的要求, 结合超磁致伸缩材料（GMM）的优良特性, 提出一种基于三角放大原理的弓张式GMM换能器。该换能器以GMM棒作为驱动元件, 通过固定弓张结构的一端, 将双向输出转变为单向输出, 同时利用柔性铰链结构, 进一步增大换能器的位移输出。通过分析换能器的工作原理, 计算得到其理论放大倍数为2.73, 与所建立的有限元仿真模型计算得到的放大倍数2.8相近。制作了试验样机并搭建了相应的试验系统, 得到在1 kHz范围内换能器最大输出位移为15.5 μm, 与仿真结果14.058 μm相近。提出的弓张结构实现了换能器的位移放大, 相应的分析方法也较好地反映了换能器的输出特性。

Combined with the quality giant magnetostrictive material (GMM), a GMM transducer with bow type structure is proposed based on the triangle amplification principle. The purpose is to improve the actuation stroke of the transducer for bigger sound intensity. At the same time, the requirements of small size of the device and less assembly parts are satisfied. This structure takes the GMM rod as the driving element. With one end of bow type structure being fixed, the bidirectional output is transformed into a one-way output. And the output displacement is further increased using the flexible hinge structure. The working principle of the transducer is analyzed. The theoretical magnification of the structure is 2.73 by analytical calculation. The result is close to that of 2.8 with the finite element simulation model. A prototype is made to be tested through the corresponding test system. And the maximum output displacement is 15.5 μm in 1 kHz range, which is close to the simulation result of 14.058 μm. The bow type structure achieves the enlarge of the transducer’s output displacement. And the corresponding analysis method has reflected the output characteristics of the transducer better.