Piezoelectric electronic-control fuel injector

Abstract

The invention aims to provide a piezoelectric electronic-control fuel injector which comprises a fuel injector body. A boss is arranged in the fuel injector body, a hole is arranged in the middle of the boss, a piezoelectric stack, a sliding fuel drain valve and a return spring of the sliding fuel drain valve are sequentially mounted on the upper side of the boss, a control piston, a return spring of a needle valve and the needle valve are sequentially mounted on the lower side of the boss, a nozzle is mounted outside the needle valve, a needle valve cavity is formed between the needle valve and the nozzle, an injection orifice is arranged at an end of the nozzle, a control chamber is formed between the control piston and the boss, a fuel storage tank and a fuel flowing hole which are communicated with each other are arranged in the sliding fuel drain valve, the fuel flowing hole is communicated with the control chamber via the hole of the boss, and a high-pressure fuel passage and a low-pressure fuel return passage are respectively arranged on the fuel injector body. The piezoelectric electronic-control fuel injector has the advantages that the piezoelectric electronic-control fuel injector is simple in structure, the piezoelectric stack is quick in response and high in driving force, the control freedom degree of the needle valve is high, the fuel charge, the fuel injection time and a fuel injection law can be flexibly and accurately controlled, repeated injection can be implemented, and the emission performance and the fuel economy of a diesel engine can be further improved.

Description

technical field [0001] The invention relates to an engine, in particular to an engine fuel injection device. Background technique [0002] With the intensification of energy crisis and environmental problems, the emission regulations of various countries are becoming increasingly strict. In order to rationally use energy, protect the environment and meet emission regulations, continuously increasing fuel injection pressure and realizing multiple injections have become the basic requirements of diesel fuel injection systems. The structure of the existing high-pressure common rail electromagnetic fuel injector for diesel engines is complicated, and due to the inductance of the solenoid valve coil, there is a certain lag time in response, which leads to further improvement of the number of fuel injections. The control accuracy of oil quantity needs to be improved. These shortcomings make the existing high-pressure common rail system unable to meet the higher requirements of fle...

AI Technical Summary

Problems solved by technology

The structure of the existing high-pressure common rail electromagnetic fuel injector for diesel engines is complicated, and due to the inductance of the solenoid valve coil, there is a certain lag time in response, which leads to further improvement of the number of fuel injections. The control accuracy of the fuel quantity needs to be improved. These shortcomings make the existing high-pressure common rail system unable to meet the higher requirements of flexible and adjustable fuel injection rate.

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