Novel electrically-controlled oil injector

Abstract

The present invention provides a novel electrically-controlled oil injector, comprising an electromagnetic valve, a control piston, a control cavity, a one-way valve, a needle valve cavity, an oil nozzle, a high-pressure oil line and a low-pressure oil line; the high-pressure oil line includes three branches, one branch leads to the control cavity through an oil inflow hole and then leads to the low-pressure oil line through an oil outflow hole, another branch leads to the oil nozzle through a lower end valve of the control piston, the remaining branch leads to the oil nozzle needle valve cavity through the one-way valve and then leads to the low-pressure oil line through a throttle hole, and the control piston is never rigidly connected with the oil nozzle. The novel electrically-controlled oil injector has the advantages that pressure of the oil nozzle needle valve cavity is turned into low pressure so that it is possible to reduce opening resistance for an oil nozzle needle valve; the control piston is used to actively control opening and closing of the high-pressure oil line leading to the oil nozzle so that it is possible to reduce closing resistance for the oil nozzle needle valve; the one-way valve is used to increase an oil line leading to the upper end control cavity of the oil nozzle so that it is possible to increase closing power for the oil nozzle needle valve. It is possible to greatly increase the opening and closing speed of the oil nozzle needle valve, thereby increasing oil injection.

Description

technical field [0001] The invention belongs to the technical field of electronically controlled fuel systems, and in particular relates to a novel electronically controlled fuel injector. Background technique [0002] With the development of processing, materials and integrated circuit technology, electronically controlled fuel system technology has become more mature and reliable, and its applicable fields are becoming wider and wider. Represented by the high-pressure common rail fuel system, it is gradually replacing electronically controlled in-line pumps, electronically controlled unit pumps and electronically controlled pump nozzles with its advantages of flexible control of fuel injection rules, independent work of fuel supply and fuel injection, and high fuel injection pressure. and other electronically controlled fuel systems. [0003] However, the core component of the existing high-pressure common rail system - the design idea of ​​the common rail injector has no...

AI Technical Summary

Problems solved by technology

[0004] The disadvantage of this structure is that the high-pressure fuel in the control chamber always acts directly on the needle valve of the fuel injection nozzle, or indirectly acts on the guide rod of the needle valve first and then acts on the needle valve of the fuel injection nozzle, which reduces the pressure of the needle valve of the fuel injection nozzle. Opening speed; at the end of fuel injection, there is always high-pressure fuel flowing to the fuel injector, which increases the closing resistance of the needle valve of the fuel injector and reduces the closing speed of the needle valve of the fuel injector; the opening speed and closing speed of the needle valve of the fuel injector It will also have the effect of "pressing oil" or "pumping oil" on the control chamber, so that the opening speed or closing speed of the needle valve of the injector nozzle is further reduced

Therefore, the shorter the fuel injection duration of the conventional common rail injector, the greater the throttling effect of the needle valve of the injector, and the lower the fuel injection efficiency of the injector

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