蜂鸣器作为警示类电子元器件,存在音量小、维修困难、使用场合少等缺点.研究了一种新型警报用机械发声装置,主要由电机、鸣轮、定轮、顶盖以及调节鸣轮和定轮之间间隙的支撑架组成.该装置以压缩空气作为声源,依赖空气振动发声.在电机高速旋转时会带动鸣轮压缩周围的空气,然后将压缩空气源源不断地挤向定轮上密集的音窗.转动时,空气从侧面和上方的进风口进入鸣轮.空气高速高压向定轮的音窗同时挤出而产生共鸣.采用 2 通道,48000 Hz的采样频率和 16 位深度麦克风开展性能测试,收集新型机械装置发声并通过数据采集系统及Friture软件进行声音波形的分析.测试结果表明,在电压平稳后,该装置在低频可以发出频率为1000~2500 Hz,输出声压级约80 dB的警报声音,具有穿透性和较好的响度级,装置在平稳运行时音量波动小且稳定.
Buzzer is one of the warning electronic components,but has some shortcomings such as low volume,difficult maintenance and fewer application occasions.A new type of mechanical sounding device for alarm is developed,which is mainly composed of a motor,a ringing wheel,a fixed wheel,a top cover and a support frame regulating the clearance between the ringing wheel and a fixed wheel.The device uses compressed air as a sound source,vibrates air to sound.When the motor rotates at high speed,it will drive the sound wheel to compress air,and then the compressed air flow continuously squeezed to the dense sound windows on the fixed wheel.Meanwhile,air will enter from the side and above the air inlet into the sound wheel.High speed and high-pressure air extrudes through the sound windows at the same time and resonates.A 2-channel,48000 Hz sampling frequency and 16-bit depth microphone is used to carry out the performance experiment,and the sound of the new mechanical device is collected and the sound waveform is analyzed by the data acquisition system and Friture software.The test results show that after the voltage is stable,the device can send out an alarm sound with a frequency of 1 000~2 500 Hz and an output sound pressure level of about 80 dB at low frequency,its penetration and loudness level are good,and the volume fluctuation of the device is small and stable when it runs smoothly.