A characteristic determining device is provided which determines fuel injection characteristics of a plurality of fuel injectors for an internal combustion engine. The characteristic determining device includes a pressure sensor and a plurality of pipes each of which connects between the pressure sensor and one of the fuel injectors. The pressure sensor is designed to have a plurality of pressure inputs from the respective fuel injectors through the pipes and outputs a signal indicative of a level of pressure in each of the fuel injectors. The characteristic determining device analyzes the signals from the first pressure sensor to determine the fuel injection characteristics of the respective fuel injectors. These arrangements result in a simplified structure of the characteristic determining device and a decreased manufacturing cost thereof.

Apparatuses and methods for fuel injection are disclosed. The apparatus includes an inner sac with one or more primary passages extending therefrom. The one or more primary passages inject fuel therethrough and comprising a first portion, a second portion, and a third portion, where the second portion is disposed between the first portion and the third portion and has a cross-sectional area smaller than that of both the first portion and the third portion. The apparatus also includes one or more secondary passages extending from an outer surface of the apparatus to fluidly couple with the second portion of the one or more primary passages. The one or more secondary passages inject air to form fuel-and-air mixture with the fuel injected from the one or more primary passages

A fuel injector includes an injector body and a valve stack within the injector body that includes a valve seat plate. The valve seat plate includes a pressure control passage for controlling fuel injection, and a valve seat positioned fluidly between the pressure control passage and a low-pressure drain. The valve seat plate includes a pressure-limiting annular groove that extends circumferentially around the valve seat and axially inward from a side of the valve seat plate where the valve seat is located. The groove enables deformation in response to pressure differences across the valve seat plate in a manner that limits stress concentrations.

An electronically controlled fuel injection device that achieves reduced component count, simplified construction, and cost reduction while promoting discharge of vapor that is generated in a pressurizing chamber. With a fuel passage from a fuel intake pipe into a pressurizing chamber and a return passage that is a discharge passage for vapor generated in the pressurizing chamber, and a plunger with a prescribed reciprocating operation having a standby position set as a position enabling fuel supply and vapor discharge, the electronically controlled fuel injection device eliminates the need for an inlet check valve and promotes the discharge of vapor that is generated when fuel is supplied from the fuel intake pipe to the pressurizing chamber.

A fuel injector includes an injector housing, an outlet check, an injection control valve assembly, and a valve seat orifice plate integrating a valve seat and various orifices for outlet check control. In the valve seat orifice plate a drain orifice extends between a valve seat surface and a check control chamber formed between a closing hydraulic surface of the outlet check and the valve seat orifice plate. First and second re-pressurization orifices extend between an outer surface of the valve seat orifice plate and the check control chamber.

A flow control system for a fuel injector of an internal combustion engine includes: an inlet channel, an outlet channel, a return channel for returning pressurized fuel to a low-pressure system having a lower pressure than the inlet channel, a fuel outlet chamber, a moveable nozzle control member in the fuel outlet chamber for selectively allowing the pressurized fuel to flow into the outlet channel, a biasing member biasing the nozzle control member towards a closed position, a moveable member defining, with the nozzle control member, a fuel control chamber configured to bias the nozzle control member towards its closed position, a moveable valve member for selectively opening and closing a flow passage and a fuel connection between the inlet channel and the fuel control chamber for pressurizing the fuel control chamber.

A fuel injection valve includes a nozzle, a housing, a needle, and a throttle portion. The nozzle includes an injection hole through which fuel is injected and a valve seat formed around the injection hole. The nozzle includes an injection hole through which fuel is injected and a valve seat formed around the injection hole. The housing has a fuel flow path through which the fuel to the injection hole flows. One end of the needle is configured to open and close the injection hole by being separated from the valve seat or abutted on the valve seat. The throttle portion is provided upstream with respect to the valve seat in a fuel flow direction.

A flow control system for a fuel injector of an internal combustion engine includes: an inlet channel, an outlet channel, a return channel for returning pressurized fuel to a low-pressure system having a lower pressure than the inlet channel, a fuel outlet chamber, a moveable nozzle control member in the fuel outlet chamber for selectively allowing the pressurized fuel to flow into the outlet channel, a biasing member biasing the nozzle control member towards a closed position, a moveable member defining, with the nozzle control member, a fuel control chamber configured to bias the nozzle control member towards its closed position, a moveable valve member for selectively opening and closing a flow passage and a fuel connection between the inlet channel and the fuel control chamber for pressurizing the fuel control chamber.

A fuel injection device injecting a fuel from an injection hole to a combustion chamber of an internal combustion engine includes a valve body including a fuel passage through which the fuel flows to the injection hole and a seat portion facing the fuel passage, a valve member moving in the valve body in an axial direction of the valve body and opening and closing the injection hole by being removed from and seated on the seat portion, a dividing member defining a pressure control chamber placed at a position opposite to the injection hole with respect to the valve member, and an outer peripheral member surrounding an exterior of an outer periphery of the dividing member. The pressure control chamber controls a movement of the valve member by a pressure of the fuel that is introduced. The outer peripheral member and the valve body constitute the fuel passage.

The housing (18) of the fuel injection valve (10) of the device for intermittently injecting fuel into the combustion chamber of an internal combustion engine comprises a high-pressure inlet (34) with a conical sealing face (44). The high-pressure chamber (36) is disposed in the housing (18) from the high-pressure inlet (34). A cartridge-like, independent component (56) is inserted into the high-pressure chamber (36). Said component comprises the valve carrier (46), the non-return valve (48), the holding element (50), and preferably the filter body (52′). The valve carrier (46) is provided with a conical outer sealing face (69), by which the valve carrier rests against the conical sealing face (44). A fixing element (74) presses the supply line (16) against the valve carrier (46).