A marine diesel fuel injector

Abstract

A fuel injector for a marine diesel engine comprises a main body (1), a plunger assembly and a solenoid valve control module. The main body (1) receives high-pressure fuel via a high-pressure fuel tube, the high-pressure fuel reaches an opening-closing plunger cavity via an internal fuel channel, and at the same time, a high-pressure servo hydraulic oil reaches a control plunger cavity via an internal oil channel. Under the action of the pressure of the high-pressure fuel and servo hydraulic oil, the opening-closing plunger (2) stops at a top dead center. A control opening of an external solenoid valve (8) is switchably connected to a high-pressure oil channel or a low pressure oil channel by using a control signal to perform rapid switching, so as to change a liquid pressure in a control chamber and a downward stroke of a control plunger (9), and in turn pressurize the servo hydraulic oil in the control plunger cavity and push the opening-closing plunger (2) to move downward, such that opening or closing of a lower end oil channel of the opening-closing plunger (2) is achieved to control fuel injection. The fuel injector effectively achieves a fast response and stable operational performance, and at the same time, the portions for electronic control and fuel injection are provided independent from each other to realize modularization for the entire fuel injector, thus facilitating maintenance and repair.

Description

technical field [0001] The invention belongs to the field of engine design, and relates to a fuel injector, in particular to an open-close type fuel injector with an external electromagnetic valve piston used in a marine diesel engine. Background technique [0002] The fuel injector of the fuel injection device, which is a key component of a diesel engine, has developed to the current electronically controlled fuel injector, which has higher requirements for the control accuracy of fuel injection timing, fuel injection law and fuel injection quantity, and has higher requirements for the manufacturing accuracy of components. And injectors have higher requirements for the applicability of different oil products. [0003] At present, the common rail fuel injector structure with built-in electromagnet and needle valve coupling is generally used to inject fuel through the opening and closing of the needle valve. It is difficult to manufacture, sensitive to oil products, and the f...

AI Technical Summary

Problems solved by technology

[0003] At present, the common rail fuel injector structure with built-in electromagnet and needle valve coupling is generally used to inject fuel through the opening and closing of the needle valve. It is difficult to manufacture, sensitive to oil products, and the fuel injector is low in modularization and difficult to maintain. poor interchangeability

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