Double-acting normally closed electronic unit pump

Abstract

The invention aims to provide a double-acting normally closed electronic unit pump; the double-acting normally closed electronic unit pump comprises a double-peach cam, a roller plunger, a normally closed fuel oil control valve, a fuel oil line reversing valve and a double oil discharge valve; the normally closed fuel oil control valve is installed above the plunger; the fuel oil line reversing valve is installed above the normally closed fuel control valve; the normally closed fuel oil control valve when not being powered on is in a normally closed state; after the normally closed fuel oil control valve is powered on, an oil drainage path is turned on by an oil drainage cone valve. By the normally closed fuel oil control valve, the supply problem of fuel oil under the conditions that an engine is powered down and the like can be solved; by reconstructing the fuel oil path at the place of the oil drainage cone valve and designing the oil path into a step shape, areas for fuel oil pressure at the two ends of the valve are changed; when an electromagnetic valve breaks down, the oil drainage cone valve is pushed open by the excessive fuel oil pressure, thereby accomplishing oil drainage and pressure releasing functions; by the normally closed fuel oil control valve with a protection device, the stability and the safety of the valve itself are improved and then the reliability of hydraulic devices such as the electronic unit pump and an oil sprayer is improved; the stability of the engine in operation is improved.

Description

technical field [0001] The invention relates to a fuel injection device, in particular to an engine fuel injection device. Background technique [0002] With the development and progress of human society, the development of modern engines has to face the dual pressures of energy crisis and environmental pollution, and the engine emission standards are constantly improving, which makes the development of engines must be in the direction of energy saving and emission reduction. The use of electronic control to realize the control of the engine fuel injection system has become the development trend of the engine, and the electronically controlled unit pump technology is an important technical means. The electronically controlled unit pump is a time-controlled fuel injection system that meets engine emission regulations and economic requirements. It has the characteristics of high fuel injection pressure and flexible and adjustable fuel injection timing. [0003] The traditiona...

AI Technical Summary

Problems solved by technology

However, the traditional electronically controlled single pump has the following disadvantages: first, the working efficiency of the single pump is low, and the camshaft can only complete the fuel supply function to one injector after one rotation of the camshaft; second, if simply changing the cam profile to double Peach cam, the fuel supplied by the camshaft for one revolution is more than the fuel injection volume of one injector, which will reduce the efficiency of the engine fuel system; third, the traditional electronically controlled unit pump can only complete the control function of a single control valve , it is difficult to meet the requirements of the engine for the fuel injection process under different working conditions; Fourth, when the solenoid valve fails and cannot be powered on, the oil drain circuit will always be open, and the normally open valve will not be able to complete the function of controlling fuel flow ; Fifth, if the solenoid valve is stuck in the closed state, the oil pressure in the valve will continue to rise, causing adverse effects on the normally open valve and the injector, resulting in damage to other hydraulic devices such as the injector

In short, the traditional electronically controlled unit pump has low working efficiency and poor safety, and cannot meet the stability of the engine, and does not have the ability to respond to failures in a timely manner.

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