piezoelectric ceramics vibration sensor are obtained by applying a DC strong electric field to a ferroelectric ceramic for polarization treatment. It is a special piezo ceramic material that can convert electrical energy and mechanical energy into each other. When the piezo ceramic is subjected to mechanical stress, it causes polarization, and the polarization value is proportional to the stress; on the contrary, when the piezo ceramic is subjected to an electric field, strain (deformation) is proportional to the electric field strength is also generated. The former effect is called the positive piezoelectric effect, and the latter is called the inverse piezoelectric effect, which are collectively referred to as the piezoelectric effect. In the positive piezoelectric effect, piezoelectric ceramics are very sensitive, and can convert extremely weak mechanical vibration into electrical signals, which can be used for sonar systems, meteorological detection, telemetry environmental protection, household appliances, and the like. In the inverse piezoelectric effect, the piezoelectric ceramic produces a small amount of deformation under the action of an electric field, up to a fraction of a millionth of its own size. This feature can be used for precision instrumentation and mechanical control, microelectronics of piezo transducer sound discs.it is technology of bioengineering and other fields. It is precisely because of these unique functions of piezoelectric ceramics that it has broad application prospects in the automotive field. This research firstly reviews the application of piezoelectric ceramics in the fields of sensing, driving, vibration isolation and noise reduction of automobiles, and then designs and fabricates a pressure detecting system for automobile tires by utilizing the power generation characteristics of piezoelectric ceramics of piezoelectric generator.
The development of piezoelectric disc element in the automotive field is that in recent years, with the rapid increase in the number of cars in China, people are increasingly demanding safety and comfort. By utilizing the piezoelectric effect of piezoelectric ceramics, functions such as sensing, driving, vibration isolation and noise reduction in the automotive field can be realized, which can meet the requirements of safety and comfort of automobiles.
Application in the field of automotive sensing:
As a source of information for automotive electronic control systems, electrical model piezoelectric discs are a key component of automotive electronic control systems. The higher is the degree of automation and automation of the car, the greater is the dependence of the sensor. A typical household car is installed with dozens to nearly a hundred sensors, and the number of sensors on a luxury car can be as many as 200. As far as the piezoelectric ceramic type sensor is concerned, a piezoelectric ceramic can be used for knocking sensor, ultrasonic sensor, and acceleration sensor, and the like are commonly used. The piezoelectric ceramic for knock sensor is composed of a piezoelectric ceramic vibrator, a metal piece, a gasket, a metal case, and the like. The electric charge generated by the piezoelectric vibrator is proportional to the vibration generated by the engine cylinder, and the generated voltage enters the electronic control unit through the shielded line, thereby detecting the voltage generated by the vibration of about 7 kHz, and the electronic control unit judges according to the magnitude of the voltage. It is detonation intensity, timely correction or corresponding delay of ignition, eliminating knocking in advance,The engine is operated at an ignition timing close to knocking, the highest thermal efficiency, and the least fuel consumption, achieving a non-knocking operation state is ensuring that the engine operates with the maximum possible power and economic indicators.
The ultrasonic sensor is used as a car reversing anti-collision alarm device, and is composed of an aluminum alloy casing, a PZT piezoceramic crystal transducer, a sound absorbing material, and a lead electrode. When an electric signal is applied to the piezoelectric ceramic, mechanical vibration is generated to emit ultrasonic waves. When the ultrasonic waves hit the obstacle during the air propagation, they are immediately reflected back. When is applied to the piezoelectric ceramic, the electrical signal is outputted through data processing. The time difference distance measurement calculates the distance between the vehicle and the obstacle and the alarm when the dangerous collision occurs. It can accurately detect the tiny obstacles in the tail of the car and the blind spot of the driver's perspective. Ultrasonic sensors are also used in automotive electronically controlled suspension systems to directly monitor the distance between the chassis and the road surface. The conical piezoelectric transducers accelerometer can be used in the automotive airbag system. The two piezoelectric ceramic sheets are bonded together through the internal common electrode to form a two-pole structure, which is mounted in the moving direction and forms a cantilever beam, and is integrated with the peripheral circuit thick film. It is made in a casing to detect the instantaneous low-speed or high-speed collision intensity of the car, and is converted into an electrical signal output. When the collision strength is large, the airbag is accurately open in time to improve the safety performance of the car.
Hubei Hannas Tech Co.,Ltd is a professional piezoelectric ceramics and ultrasonic transducer manufacturer, dedicated to ultrasonic technology and industrial applications.
