压电陶瓷蜂鸣片的构造及发音原理
日期:2009-08-21 08:53:01来源:点击:911 次
压电陶瓷蜂鸣片的构造及发音原理:
压电陶瓷蜂鸣片是将高压极压化后的压电陶瓷片黏贴于振动金属片(一般有铜片,铁片,不锈钢,铝片等)上。
当加入交流电压后,会因为压电效应,而产生机械变形伸展及收缩,利用此特性使金属片振动而发出声响。
压电陶瓷蜂鸣片一般分为他激式(二极);自激式(三极)两种。
详细的分类见:行业新闻→蜂鸣片的分类↔http://www.ke-sen.com/news/industry_news/214.html
1、Oscillating system 工作原理
Fig 1 shows the structure of piezoelectric diaphragm.
Fig 2 shows the oscillating system of a piezoelectric diaphragm.when AC voltage is applied across electrodes, the bending shownin Fig 2(a) and Fig 2(b) is repeated as shown in Fig 2(c),producing sound waves in the air.z
2、Soldering procedures 焊接要求
When using a soldering iron, the optimum temperature for soldering alead wire to a metal plate is 340℃± 10℃for 1-2 second and thesame temperature for the ceramic Silver electrode for 0.5 second orless. Drive procedures for Piezoelectric sound components include (i)external drive (ii) self drive as shown in Fig 3.
A. Test Condition: Solder DotHigh 1.5mm MAX Diameter 2.5mm-3.0mm MAX
B. Characteristics
3、Measuring Contents 测试内容
4、Measuring Procedure 测试方法
Measurement of resonant frequency and resonant impedance. When the Piezoelectric diaphragm
oscillates freely in air, the node does not move as shown in Fig. 6. With this point held with a
measuring terminal, the resonant frequency and resonant impedance are measured in the Constant- current circuit.
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