压电式加速度传感器,又称振动传感器,是基于压电晶体的压电效应工作的。某些晶体在一定方向上受力变形时,其内部会产生极化现象,同时在它的两个表面上产生符号相反的电荷;当外力去除后,又重新恢复到不带电状态,这种现象称为“压电效应",具有“压电效应"的晶体称为压电晶体。常用的压电晶体有石英、压电陶瓷等,在现代生产生活中被应用于许许多多的方面,如手提电脑的硬盘抗摔保护,目前用的数码相机和摄像机里,也有加速度传感器,用来检测拍摄时候的手部的振动,并根据这些振动,自动调节相机的聚焦。压电加速度传感器还应用于汽车安全气囊、防抱死系统、牵引控制系统等安全性能方面。
美国Dytran的3221C是一款高温型加速度传感器/振动传感器,具有体积小、结构坚固,高密封、耐高温等特点,高频率,工作温度高达260℃。
The Dytran 3221C is a ring style high temperature piezoelectric charge mode accelerometer offering a high natural frequency and reliable operation in temperatures up to +500°F (+260°C).
Incorporating a unique single crystal piezoelectric sensing element operating in shear mode, the Dytran model 3221C is offered with a sensitivity of 10 pC/g. Units feature a radial 10-32 side connector, as well as a miniature thru hole design, allowing the sensor to be turned 360° prior to securing, aiding the user during sensor installation. The model 3221C is also hermetically sealed for use in demanding environments, and base isolated to avoid EMI/ground loop interference.
特性
1. 10 pC/g sensitivity
2. 10,000 Hz upper frequency range (±10%)
3. 10-32 side connector
4. Ø.140 thru hole mount
5. 9.0 grams
6. Titanium
7. Hermetic
8. Base isolated
9. 360° cable orientation
10. +500°F (+260°C) operation
11. Charge mode
应用
1. Aerospace and flight testing
航空航天与飞行试验
2. High temperature vibration measurements on small structures and objects
小物体高温振动测试
Weight, Max 0.32 oz 9.0 grams
Sensitivity, +/-20% [2] [3] 10 pC/g 1.02 pC / m/s2
Range F.S +/-500 g +/-4900 m/s2
Frequency Response, +/- 10% [5] to 10000 Hz [5] to 10000 Hz
Mounted Resonant Frequency kHz >kHz
Amplitude Non-Linearity 1 %F.S MAX 1 %F.S MAX
Transverse Sensitivity, Max 5 % 5 %
Strain Sensitivity @250/μσ 0.08 g/με 0.78 m/s2 /με
ENVIRONMENTAL
Maximum Vibration 700 g rms 6860 m/s2 rms
Maximum Shock 5000 g 49000 m/s2
Temperature Range -60 to +500 °F -51 to + 260 °C
Environmental Seal Hermetic Hermetic
ELECTRICAL
Output Signal Polarity Positive Positive
Case Grounding Case is grounded Case is grounded
Base Grounding Base is isolated Base is isolated