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振动分析

特性:

KLIPPEL R&D系统
累积加速度级AAL SCN
模态分析 (固有频率、模态损耗因子、模式形状) SCN, RMAHMA
径向和周向模式 SCN
摇摆模式 SCN, RMA

以足够分辨率在辐射器表面上点r处通过激光扫描测量的传递函数Hc(jω, φ, rc)和几何形状是进行机械分析的基础。下图显示了使用累积加速度AAL对扬声器音盆进行模态分析的原理,该AAL包含了辐射器上的总机械振动。在低频处,辐射器像一个刚性物体一样振动,此时AAL与SPL相同。
固有频率、损耗因子和在径向和周向上传播的振动形状为诊断 (如找出摇摆模式)和实际改进 (例如施加额外的阻尼并更改材料和几何形状)提供基础.


模组

备注

扫描振动系统 (SCN)

SCN 以后处理的方式执行机械振动分析,不需要硬件 (仅需电子狗).

高阶模态分析 (HMA)

使用激光扫描仪进行自动测量识别模态参数 (模态共振频率、阻尼、增益)和特征振动模式 (模式形状)。这将膜片上复杂的振动模式分为易于理解的单个振动分量,可以研究模式的相互作用及其对声辐射和响应的影响,并可以识别出无益的振动模式。模态参数可用于调整具有相同"模态视图"的有限元模型。
该模块提供了膜片形变的动画视图,以定位非线性失真的潜在来源.

摇摆模式分析 (RMA)

使用激光扫描仪进行自动测量识别摇摆模式的根本原因。对质量、刚性和力因数的不平衡进行量化,并揭示每个不平衡中心在振膜上的位置.这在避免驱动单元不稳定、音圈摩擦和脉冲失真以及确保生产一致性方面很有用。特别适用于微型扬声器和耳机换能器.

示例:

模态分析是查找和评估周向模式 (摇摆模式)的理想工具,摇摆模式是音圈在ci隙中摩擦的主要原因。此模式的累计加速度级 (AAL)应该比
模态分析是查找和评估周向模式 (摇摆模式)的理想工具,摇摆模式是音圈在磁隙中摩擦的主要原因。此模式的累计加速度级 (AAL)应该比总振动的AAL小很多。
累积加速度级AAL的模态共振处的3dB带宽揭示了材料的模态损耗因子η(f).η(f)的值越低,要求材料的阻尼越高,或执行高振动时需要对材料进行涂层。
累积加速度级AAL的模态共振处的3dB带宽揭示了材料的模态损耗因子η(f).η(f)的值越低,要求材料的阻尼越高,或执行高振动时需要对材料进行涂层。


KLIPPEL产品模板

TRF扫描音盆振动
使用具有高截止频率 (>15 kHz)的激光传感器手动扫描音盆振动


标准

音频工程学会
AES2 Recommended practice Specification of Loudspeaker Components Used in Professional Audio and Sound Reinforcement (AES2推荐的用于专业音频和声音增强的扬声器组件的实用规范)

国际电工委员会
IEC 60268-5 Sound System Equipment, Part 5: Loudspeakers ( IEC 60268-5声音系统设备,第5部分: 扬声器)




论文和预印本

W. Klippel, et al., “Distributed Mechanical Parameters of Loudspeakers Part 1: Measurement,” J. of Audio Eng. Soc. 57, No. 9, pp. 500-511 (2009 Sept.).

W. Klippel, et al., “Distributed Mechanical Parameters of Loudspeakers Part 2: Diagnostics,” J. of Audio Eng. Soc. 57, No. 9, pp. 696-708 (2009 Sept.).

F. J. M. Frankort, “Vibration Patterns and Radiation Behavior of Loudspeaker Cones,” J. of Audio Eng. Soc., Volume 26, No. 9, pp. 609-622 (September 1978).

J. R. Wright, “Automatic Vibration Analysis by Laser Interferometry,” presented at the 88th Convention of the Audio Eng. Soc., Preprint 2889, (March 1990).

A. J. M. Kaizer, “Theory and Numerical Calculation of the Vibration and Sound Radiation of Cone and Dome Loudspeakers with Non-Rigid Diaphragms,” presented at the 62nd Convention of the Audio Eng. Soc., March 1979, Preprint 1437.

C. Struck, “Analysis of the Nonrigid Behavior of a Loudspeaker Diaphragm using Modal Analysis,” presented at 86th convention of Audio Eng. Soc., Hamburg, Preprint 2779 (1989).

A. Chaigne, et al., “On the Influence of the Geometry on Radiation Electrodynamic Loudspeakers,”    presented at the 120th Convention of the Audio Eng. Soc., (May 2006), Preprint 6775.

P. J. Anthony, et al., “Finite-Element Analysis in the Design of High-Quality Loudspeakers,” presented at the 108th Convention of the Audio Eng. Soc., February 2000, Preprint 5162.

M. Karjalainen, et al., “Comparison of Numerical Simulation Models and Measured Low-Frequency Behavior of a Loudspeaker,” presented at the 104th Convention of the Audio Eng. Soc., May 1998, Preprint 4722.

J. Wright, “Finite Element Analysis as a Loudspeaker Design Tool,” Paper MAL-11; Conference: AES UK Conference: Microphones & Loudspeakers, The Ins & Outs of Audio (MAL), March 1998.

H. Vollesen, “Control of Loudspeaker Directivity by Mechanical Optimization of the Diaphragm,” presented at the 94th Convention of the Audio Eng. Soc., March 1993, Preprint 3528.

S. Morita, “Acoustic Radiation of a Horn Loudspeaker by the Finite Element Method - A Consideration of the Acoustic Characteristic of Horns,” J. of Audio Eng. Soc., Volume 28, No. 7/8, pp. 482-489, July 1980.

A. Kaizer, “Calculation of the Sound Radiation of a Nonrigid Loudspeaker Diaphragm Using the Finite-Element Method,” J. of Audio Eng. Soc., Volume 36, No. 7/8, pp. 539-551; July 1988.

A. Bright, “Vibration Behaviour of Single-Suspension Electrodynamic Loudspeakers,” presented at the 109th Convention of the Audio Eng. Soc., (September 2000), Preprint 5213.

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