A fuel inlet of a common rail fuel injector

Abstract

The invention discloses an oil inlet of a common rail injector. The oil inlet of the common rail injector is oil ways between an oil inlet horizontal cavity between the high-pressure oil cavity inside the injector and comprises an oil way a on the outermost side of an injector body, and an oil way b inside the injector body; the oil way a is connected with the oil inlet horizontal cavity of the injector, and the oil way b is connected with the high-pressure oil cavity inside the ejector; the oil way a is in the shape of a reducing cone in the fuel flowing direction, and the oil way is of an increasing structure in the direction perpendicular to the axis of the ejector body; the first section of the oil way a is used for connecting the oil inlet horizontal cavity to ensure sealing of high-pressure fuel; a kidney-shaped-hole structure of the oil way b enables more fuel to flow towards both sides of a control piston and reduces fuel directly flowing towards the control piston from the front surface; meanwhile, the increasing structure of the oil way b further enables the high-pressure fuel to flow towards both sides of the control piston and further avoids direct impact of the high-pressure fuel onto the control piston. Therefore, the oil inlet of the common rail ejector can reduce the lateral impact force born by the control piston, effectively avoid instability of the control piston and improve the working stability of the ejector.

Description

technical field [0001] The invention belongs to the field of fuel injection systems of internal combustion engines, and in particular relates to an oil inlet structure of a common rail fuel injector. Background technique [0002] As the injection pressure of the common rail system increases, the injector begins to adopt a non-static oil return design. Moving parts such as control pistons and needle valves are completely immersed in high-pressure fuel, and many injector control pistons and needle valves are integrated into one structure. High-pressure fuel enters the high-pressure chamber of the injector body through the inlet of the cylindrical injector, and most of the high-pressure fuel will directly impact the control piston due to the guidance of the cylindrical oil passage, generating a lateral impact on the control piston. Because the length of the control piston is relatively large, especially after the control piston and the needle valve are made into an integrated ...

AI Technical Summary

Problems solved by technology

Because the length of the control piston is relatively large, especially after the control piston and the needle valve are made into an integrated structure, it is easy to lose stability or be biased by the repeated high-frequency impact of fuel (one impact every time the oil is injected)

As a result, the injector is unstable and affects the performance of the injector

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