Last Updated on April 6, 2023 by You Ling
Application of Piezoelectric Ceramics in piezoelectric injector
What is piezoelectric injector?
A piezoelectric injector, also known as a piezo injector, is a type of fuel injector used in internal combustion engines. It uses a piezoelectric actuator to precisely control the injection of fuel into the engine cylinders. When an electrical charge is applied to the piezoelectric material, it changes shape, creating a force that is used to open the injector valve and allow fuel to be sprayed into the engine. The precise control offered by piezoelectric injectors can result in improved fuel efficiency, reduced emissions, and better engine performance compared to other types of fuel injectors. They are commonly used in diesel engines and some gasoline engines.
How piezoelectric injector works?
Piezoelectric injectors work by using a piezoelectric crystal to control the opening and closing of the injector valve. The crystal is made of a special material that produces an electric charge when it is mechanically deformed or vibrated. When a voltage is applied to the crystal, it undergoes a small deformation that opens the injector valve and allows fuel to be injected into the engine cylinder.
The piezoelectric crystal is attached to a stack of small metal discs, which amplify the movement of the crystal and help to open the injector valve more quickly and precisely. When the voltage is removed from the crystal, it returns to its original shape and closes the injector valve, stopping the flow of fuel.
The use of piezoelectric crystals in injectors allows for very precise control over the amount of fuel injected into the engine, which can improve fuel efficiency, reduce emissions, and improve engine performance. Piezoelectric injectors are commonly used in diesel engines, where the high pressure of the fuel requires precise control to ensure efficient combustion.
Which piezo elements can be used for piezoelectric injector?
Piezo elements used in piezoelectric injectors are typically made of lead zirconate titanate (PZT) ceramics, which are capable of producing strong, predictable movements when subjected to an electrical field. The specific type of PZT used for piezoelectric injectors will depend on the specific application, but commonly used materials include PZT-4, PZT-5A, and PZT-5H. These materials have different properties, such as their dielectric constant, piezoelectric charge coefficient, and mechanical quality factor, which can affect the performance of the injector. The choice of piezo element will depend on the specific requirements of the injector, such as the desired flow rate, response time, and durability.