H形质量块对压电悬臂梁应变分布的均匀化

H-shaped Proof Mass Smoothes Strain Distribution of Piezoelectric Cantilever

提出了一种新型悬臂梁式压电能量回收结构。该结构由普通的矩形梁和H形质量块构成。H形质量块包括两块分离的金属块,它们可提供较大的转动惯量。当受到激励时,H形质量块将在悬臂梁的自由端产生弯矩。通过选择两个分离金属块合适的质量比和整个结构合适的振动模态,悬臂梁的纵向应力分布将趋向均匀一致。分析了该结构并制作了一个原型进行了测试。实验结果同有限元分析一致。

This paper proposes a novel cantilever piezoelectric energy harvester. The structure is composed of an ordinary rectangular beam and H-shaped proof mass which can smooth the strain distribution. The H-shaped proof mass contains two pieces of detached metal blocks that can provide large rotary inertia. Bending moment at the tip of the cantilever may be generated through the H-shaped proof mass when the base is activated. By selecting an appro- priate mass ratio between the detached metal blocks and vibration mode, strain distribution along the cantilever hecomes rather uniform. A prototype structure is analyzed,manufactured,and tested. The experimental result is identical with the analysis using finite element method.