Double-path oil inlet bypass electric control oil sprayer with carving grooves

Abstract

The invention aims at providing a double-path oil inlet bypass electric control oil sprayer with carving grooves. The double-path oil inlet bypass electric control oil sprayer comprises an oil sprayer head, an oil sprayer body, a current limiting valve assembly, an electromagnetic valve assembly, a needle valve assembly, a needle valve seat and a spray nozzle, wherein the current limiting valve assembly is positioned inside a pressure accumulation cavity to guarantee the stable oil spraying process of each cylinder under the condition of great oil spraying quantity. The electromagnetic valve assembly and the needle valve assembly are arranged at the lower side. The electromagnetic valve uses a two-position three-way form so as to reduce the dynamic oil return quantity. A control slide block is arranged inside the control cavity, and is in contact with an intermediate block; the effects of decelerating the oil spraying speed at the primary spraying stage and accelerating the needle valve seating response are achieved. An oil inlet throttle hole is formed in the control slide block; the control cavity pressure building is further accelerated. The carving grooves in the micrometer levels are formed in the surface of the spray needle valve body; the stability of the cavitation flowing can be effectively improved; the cavitation erosion degree of the oil sprayer is reduced. A control plunger piston structure of the oil sprayer is omitted, so that no static pressure difference exists at the inside of the oil sprayer; the characteristic of no static leakage of the oil sprayer is ensured.

Description

technical field [0001] The invention relates to an engine fuel injection device. Background technique [0002] The high-speed solenoid valve injector, which is widely used at present, has the advantages of fast system response, high control precision, flexible control strategy and reliable working performance. However, since most high-speed solenoid valve injectors adopt the form of a two-position two-way solenoid valve and a single-way oil inlet, the quick response function cannot be realized. In the fuel injector, the restrictive conditions for the selection of the orifice diameter of the oil inlet orifice and the oil outlet orifice also make it difficult to further improve the performance of the fuel injector: when the diameter of the oil inlet orifice is too small, the oil pressure in the control chamber will The speed slows down, and the needle valve seat is delayed, which increases the emission of particulate matter. When the diameter of the oil inlet orifice is too ...

AI Technical Summary

Problems solved by technology

However, since most high-speed solenoid valve injectors adopt the form of a two-position two-way solenoid valve and a single-way oil inlet, it cannot achieve a quick response function

In the fuel injector, the restrictions on the selection of the orifice diameters of the oil inlet orifice and the oil outlet orifice also make it difficult to further improve the performance of the fuel injector: when the oil inlet orifice diameter is too small, the oil pressure in the control chamber will The speed slows down and the needle valve seat is delayed, which increases the emission of particulate matter

When the diameter of the oil inlet orifice is too large, due to the principle that the diameter of the oil outlet orifice is larger than that of the oil inlet orifice, although the response speed of the needle valve seating is greatly improved, the dynamic oil return during the fuel injection process is increased. Energy loss also increases

At the same time, the increase in the diameter of the oil outlet orifice will also cause the injection speed to be too fast, resulting in an increase in the emission of nitrogen oxides

In addition, due to the existence of the control plunger, there is a static pressure difference in the fuel injector, resulting in static fuel leakage and affecting the work of the fuel injector

When the injector injects a large amount of oil, the oil pressure in the high-pressure common rail tends to fluctuate, resulting in inconsistencies in the working process of each cylinder

As the work of the injector increases gradually and the flow rate increases, the degree of cavitation and cavitation in the injector increases significantly, and the reliability of the injector decreases.

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