An impact type accelerometer is a sensor used to measure the instantaneous acceleration of an object when it is impacted or impacted. Based on the principle of inertia and electronic signal processing technology, the core structure includes a measuring mass block (sensitive mass block). When an object is subjected to acceleration or impact, the mass block undergoes displacement due to inertia, and the sensor detects this displacement change and converts it into an electrical signal output. The specific implementation methods include:
Piezoelectric effect: When piezoelectric materials (such as quartz and piezoelectric ceramics) are impacted and deformed, the internal charge distribution changes, directly outputting a charge signal proportional to the acceleration.
Piezoresistive effect: The deformation of semiconductor or metal materials causes a change in resistance, which is converted into a voltage signal through a Wheatstone bridge circuit.
Capacitance change: The distance between the movable electrode and the fixed electrode changes, and the capacitance value changes, which is converted into an acceleration signal through the circuit.
MEMS technology: Based on silicon microfabrication technology, acceleration measurement is achieved by detecting microstructure displacement (such as capacitance or piezoresistive changes).
Key points for installation and use
Installation stiffness: The sensor should be tightly attached to the object being measured to avoid "loose installation" (such as not tightened or not firmly bonded), otherwise it will cause frequency response attenuation and inaccurate peak measurement;
Grounding treatment: ICP type sensors need to be grounded at a single point to avoid electromagnetic interference (such as near motors and frequency converters), and signal cables should use shielded wires;
Calibration cycle: Industrial testing is calibrated every 6-12 months, and scientific research testing is calibrated every 3-6 months (using an impact calibration bench, calibration parameters: sensitivity, range linearity);
Cable selection: In impact testing, the sensor may move with the object being tested, so a flexible shielded cable (such as silicone wire) is needed to avoid signal distortion caused by cable pulling.
The core selection logic of impact type acceleration sensors is "matching impact range+frequency response coverage+scene adaptation": ICP type is preferred for industrial conventional testing (convenient anti-interference), charge type (high-resolution) is selected for scientific research high-frequency impact, and MEMS type is selected for batch low-cost testing. When using, special attention should be paid to installation stiffness, calibration cycle, and signal anti-interference to avoid measurement errors caused by improper selection or operation.