Two-way needle control valve

Abstract

The invention discloses a two-way needle control valve for controlling a needle position of a needle valve in a fuel injector. A lifting structural member is configured to move between an open position and a closed position in a valve hole of a valve body; the valve hole comprises a discharging part; when the valve is at the open position, the discharging part discharges fuel from the valve; the valve comprises a supply pipeline extending to penetrate through at least one part of the valve body; the supply pipeline receives the fuel from a high-pressure fuel pipeline; an inlet throttling pipeline is communicated with the supply pipeline through fluid and conveys the fuel from the supply pipeline to a control cavity in a throttling plate; an outlet throttling pipeline conveys the fuel from the control cavity to a valve body inlet pipeline; the valve body inlet pipeline is configured to convey the fuel to a cavity in the valve hole.

Description

technical field [0001] This application claims the benefit of priority to US Patent Application No. 61 / 567,197, filed December 6, 2011, which is hereby incorporated by reference in its entirety. [0002] The present invention relates to a two-way needle control valve used in a fuel injector. Background technique [0003] High pressure fuel injection systems are often used in internal combustion engines to deliver fuel to the combustion chamber. Fuel may be supplied to a series of unit fuel injectors through a common rail. Fuel injectors typically utilize needle valves to inject fuel into the combustion chamber. When pressurized fuel to be injected into the combustion chamber is supplied to the nozzle chamber of the injector, the pressurized fuel may act on the needle of the needle valve in a direction which attempts to lift the needle to an open position. To balance such forces, the fuel injector may include a region above the needle where a controlled volume of pressuriz...

AI Technical Summary

Problems solved by technology

However, given the tight dimensional tolerances required for the control valve 100 to provide the necessary sealing, such a configuration may have potential alignment problems, for example, between the upper and lower guides 118, 120 and adjacent portions of the valve bore 108. between

Such alignment issues can interfere with the movement of the lift member 106, which can hinder the response time of the needle 130 to initiate and terminate movement to inject fuel into the combustion chamber

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