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Application of piezoelectric sensors in automotive fuel vapour management systems

Application of piezoelectric sensors in automotive fuel vapour management systems

(Summary description)The car has fully entered our lives and most of our daily travels depend on it. Every part of the car is precisely controlled by an automotive piezoelectric sensor, so what is an automotive pressure sensor? What are some examples of applications for automotive pressure sensors?

Application of piezoelectric sensors in automotive fuel vapour management systems

(Summary description)The car has fully entered our lives and most of our daily travels depend on it. Every part of the car is precisely controlled by an automotive piezoelectric sensor, so what is an automotive pressure sensor? What are some examples of applications for automotive pressure sensors?

Information

The car has fully entered our lives and most of our daily travels depend on it. Every part of the car is precisely controlled by an automotive piezoelectric sensor, so what is an automotive pressure sensor? What are some examples of applications for automotive pressure sensors?

 

An automotive piezoelectric sensor is used to control the oil pressure of a braking system with an oil pressure booster. It detects the pressure of the accumulator, outputs a signal to turn the oil pump off or on, and warns of abnormal oil pressure. It is equipped with a semiconductor strain gauge, which is characterised by a change in the resistance of the strain gauge when the shape changes; the pressure sensor also has a metal diaphragm, where pressure changes are detected by the metal diaphragm strain gauge and converted into an electrical signal for external output.

 

Piezoelectric sensor fuel vapour management systems:

 

As fuel vapour is one of the main causes of hydrocarbon emissions, fuel vapour is emitted directly into the atmosphere when the vehicle is refuelled at a petrol station, which is environmentally unfriendly and a waste of fuel. The activated carbon canister is porous and has a large surface area which allows it to absorb a large number of fuel vapour molecules.

 

The activated carbon tank is connected to the engine's intake manifold, where the movement of the piston causes a low pressure to be generated when the engine is running on the intake stroke. The air passes through the activated carbon canister under the suction of the low pressure of the intake manifold.

 

The fuel vapour molecules adsorbed in the medium are sent to the engine for combustion so that they can be fully utilised and the adsorption capacity of the activated carbon in the canister is restored. The fuel vapour management system requires a miniature piezoelectric sensor (gauge pressure mode) to detect fuel vapour leaks.

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