At present, in order to ensure the safety of the car driving, many car tires are equipped with pressure sensors to detect the change of pressure, according to the relevant data statistics, tire pressure reached a reasonable value, not only can improve the safety of driving, but also can save fuel consumption. So how doesthe tire pressure sensorwork?
Tire pressure monitoring system mainly has two kinds of solutions, direct system and indirect system.
The direct tire pressure monitoring system uses the pressure sensor installed in each tire to directly measure the tire pressure, and the tire pressure is displayed and monitored, when the tire pressure is too low or there is leakage, the system will automatically alarm.
Direct tire pressure monitoring system is divided into two types: active and passive.
Active system is made by using mems technology on silicon capacitive or piezoresistive pressure sensor, the pressure sensor installed on each wheel rim, transmit through radio frequency signal, installed in the cab of the wireless receiver receives the pressure sensitive signals, after a certain signal processing, shows the tire pressure.
The indirect tire pressure monitoring system compares the speed difference between tires through the wheel speed sensor of automobile ABS system to achieve the purpose of monitoring tire pressure. The main disadvantages of this type of system are:
1, can not display the accurate instantaneous pressure value of each tire;
2. When the pressure of the same axle or wheel on the same side or all tires drops at the same time, the alarm cannot be given;
3, can not take into account the speed, detection accuracy and other factors.