Control valve for oil atomizer

Abstract

The invention relates to a control valve for an oil atomizer. The control valve comprises electromagnets, a sealing bolt pin, electromagnet springs, an armature, an armature guide rod, control valve bases, a restriction orifice and an oil atomizer body. The control valve is characterized in that the sealing bolt pin is arranged in inner holes of the control valve bases; a high-pressure sealing face is formed by the outer circle surface of the sealing bolt pin and the inner holes of the control valve bases; a valve chamber is defined by the sealing bolt pin, the control valve base and the restriction orifice and is communicated with a control chamber through an oil outlet path; the sealing bolt pin is in rigid connection with the armature guide rod and is pressed on a supporting face at the upper end of the restriction orifice under downward elastic force of the electromagnet springs; a closed portion is arranged on the lower end face of the sealing bolt pin; a high-pressure sealing face is formed by the supporting face of the lower end of the closed portion and the supporting face of the upper end of the restriction orifice; a blind hole is formed in the center of the restriction orifice; an oil returning cavity is formed between the blind hole and the lower end face of the sealing bolt pin and is communicated with an oil returning channel. The control valve can be closed only through small spring pre-tightening force.

Description

technical field [0001] The invention relates to a control valve for a fuel injector, in particular to a pressure-balanced control valve for a fuel injector, which belongs to the field of diesel engine fuel injection systems. Background technique [0002] At present, the commonly used control valve forms of diesel engine injectors in my country mainly include ball valve (US7866575 B2) of Bosch company and planar valve (US2012 / 0012680 A1) of Denso company, both of which are pressure unbalanced control valves. The high-pressure fuel acts on the ball valve or plane valve to generate a certain fuel pressure. In order to close the oil circuit, a spring preload force greater than this fuel pressure and in the opposite direction is required to act on the control valve. In order to open the oil circuit, a more Large electromagnet attraction to overcome this spring force. As the system pressure rises, the fuel pressure acting on the valve rises, the spring preload increases according...

AI Technical Summary

Problems solved by technology

Moreover, it is more difficult for the electromagnet to control the control valve, the opening delay of fuel injection is increased, the stroke of the control valve is difficult to control, the precision of fuel injection is reduced, and the ability of multiple injections is reduced

[0003] In recent years, many companies have adopted pressure-balanced control valves, such as the slide valve structure of Delphi Company. Balanced, but the armature guide rod of this structure has high processing and manufacturing costs, and with the accumulation of service time, it will bring high cost replacement and maintenance costs due to wear; the line-sealed cone valve structure of Bosch Company (US 7870847 B2 , CN 101535625A), the armature is used to seal the control valve seat, and a hydraulic balance control chamber is constructed with the guide rod. Similarly, due to the limitations of the cone valve structure itself, there are great deficiencies in reliability and durability

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