Working Principle Of Vacorda Pressure Transmitter Sensor
Author:Vacorda Source:www.vacorda.com Date: 2020-08-28 14:00:06
The pressure sensor is manufactured by us using the piezoelectric effect, which is also a piezoelectric sensor.
We know that crystals are anisotropic and non-crystals are isotropic. Certain crystal media, when deformed by mechanical force along a certain direction, have a polarization effect. The pressure sensor is developed by scientists based on this effect.
Quartz, dihydrogen phosphate and potassium sodium tartrate are the main piezoelectric materials used in piezoelectric sensors. Among them, quartz (silica) is a natural crystal, the temperature is controlled within a certain range, and the piezoelectric properties are stable, but after the temperature exceeds the limit, the piezoelectric properties completely disappear (this high temperature is the so-called "Curie point"). As the electric field changes slightly with the change of stress (that is, the piezoelectric coefficient is relatively low), quartz is gradually replaced by other piezoelectric crystals. Potassium sodium tartrate has great piezoelectric sensitivity and piezoelectric coefficient, but it can only be used in environments where room temperature and humidity are relatively low. Dihydrogen phosphate is an artificial crystal that can withstand high temperatures and relatively high humidity, so it has been widely used.
At present, the piezoelectric effect is also applied to polycrystals, such as current piezoelectric ceramics, including barium titanate piezoelectric ceramics, PZT, niobate piezoelectric ceramics, lead magnesium niobate piezoelectric ceramics, and so on.
The piezoelectric effect is the main working principle of the piezoelectric sensor. The piezoelectric sensor cannot be used for static measurement, because the electric charge after the action of the external force can only be saved when the circuit has an infinite input impedance. The actual situation is not like this, so this determines that the piezoelectric sensor can only measure dynamic stress.
Piezoelectric sensors are mainly used in the measurement of acceleration, pressure and force. The piezoelectric accelerometer is a commonly used accelerometer. It has the advantages of simple structure, small size, light weight and long service life. It can also be used in the military industry. For example, it can be used to measure the change of the pressure in the chamber and the shock wave pressure of the muzzle at the moment of firing. It can be used to measure large pressures as well as small pressures.
Piezoelectric sensors are also widely used in biomedical measurement. For example, ventricular catheter microphones are made of piezoelectric sensors. Because the measurement of dynamic pressure is so common, the application of piezoelectric sensors is very wide.