A valve assembly for an injection valve is disclosed. The valve assembly includes a valve body having a cavity with a fluid inlet portion and a fluid outlet portion, a valve needle, an armature which is able to slide on the valve needle, and a disc element positioned to limit axial displaceability of the armature relative to the valve needle. The disc element includes a plurality of passages extending in axial direction through a disc-shaped part of the disc element. The passages provide a first flow resistance for a fluid passing in a direction away from the fluid outlet passage and a second flow resistance in a direction towards the fluid outlet passage, wherein the second flow resistance is larger than the first flow resistance.

Provided is a prestroke adjustment method for a fuel injection valve capable of reducing variations in a prestroke amount regardless of the level of machining accuracy of a component. The prestroke adjustment method adjusts a prestroke amount D2 of a fuel injection valve 1 including a gap forming member 50 that forms a gap G2 defining a prestroke between a valve member 30 and engagement portions 33a and 423a of a movable core 42 by a second portion 52a abutting on the movable core 42 in a state where a first portion 51a is positioned at a reference position 33b of the valve member 30. In the prestroke adjustment method, a load L in the direction from the first portion 51a toward the reference position 33b of the valve member 30 is applied to the gap forming member 50 assembled to the valve member 30 to plastically deform the gap forming member 50, thereby shortening the relative length between the first portion 51a and the second portion 52a and setting the prestroke amount D2 to the target value T2.

A gas injector for injecting a gaseous fuel, in particular directly into a combustion chamber of an internal combustion engine, including: a valve closing element for opening or closing a pass-through opening, a valve body, and a sealing seat between the valve body and the valve closing element, in the case of a maximum lift of the valve closing element a flow cross section between the valve body and the valve closing element being smaller in the flow direction upstream from the sealing seat than a flow cross section between the valve closing element and the sealing seat and being smaller than a flow cross section in the flow direction downstream from the sealing seat.

A fuel injector is provided that creates variable spray characteristics to effectively reduce emissions, such as NOx emissions and particulate matter. The injector includes a nozzle valve element of the outwardly opening type including a fuel delivery passage and spray holes. The nozzle valve element is operable to move to a low lift position to cause fuel flowing from the spray holes to impinge on the injector body and to deflect toward the combustion chamber, and to move to a high lift position to cause fuel flowing from the spray holes to avoid impingement on injector body and flow in an obstructed manner directly into the combustion chamber. An annular chamber may be formed in the nozzle valve element adjacent the spray holes to receive fuel.

An injector is designed to provide continuously variable injection rate shaping. With a hydro-mechanical internal feedback mechanism, injector needle position can be determined by controlling a feedback valve's on/off timing. According to the needle position, an injection needle valve opening can be controlled, and then the injection flow rate can be delivered proportionally. Also in accordance with the present invention a CRDI systems are provided including injectors of the present invention, wherein results demonstrate that injector designs of the present invention not only achieve rate shaping capability but also solve the above-noted problems of the current CRDI system. Finally, an iterative learning controller has also been developed to track the desired injection rate, and an injection rate estimator is designed to realize a cycle to cycle feedback control.

The invention provides a valve having an elongated main body and a substantially flat area defined within the valve between its first and second ends; wherein a stopping screw is received in said flat area so as to prevent extraction of the valve from a casing by applying a force against a portion of the valve once the valve is moved a predetermined number of turns. The invention also provides a method for inhibiting the turning of a valve having the steps of installing a threaded portion of a valve in a first threaded aperture through a casing, where the first threaded aperture receives the threads of the threaded portion of the valve; and threading a screw through a second threaded aperture in an exterior of the casing, where the screw, is disposed in a position to come into direct contact with the valve after a predetermined number of turns.

An electromagnetic valve used in a fuel system, in which at least a portion of a member constituting an magnetic circuit in an electromagnetic drive unit includes 0.15-0.45 mass % (inclusive) Ni, 0.65-1.0 mass % (inclusive) Al, 9.2-10.3 mass % (inclusive) Cr, and 0.90-1.6 mass % (inclusive) Mo, and the remainder comprises an alloy material comprising Fe and unavoidable impurities. The alloy material may further include 0.05-0.15 mass % (inclusive) Pb.

A pressure detection unit detects a fuel pressure in high-pressure fuel passages. A drive control unit controls opening and closing of pressure adjusting valves based on a drive command signal output to the fuel injection valve. An acquisition unit acquires an inflection point of the fuel pressure detected by the pressure detection unit and an inclination of the fuel pressure after the inflection point appears, after an output of the drive command signal. A delay time computation unit computes a response delay time of the pressure adjusting valve with respect to the drive command signal for each of the first on-off valve and the second on-off valve based on the inflection point and the inclination acquired by the acquisition unit.

A pressure detection unit detects a fuel pressure in high-pressure fuel passages. A drive control unit controls opening and closing of pressure adjusting valves based on a drive command signal output to the fuel injection valve. An acquisition unit acquires an inflection point of the fuel pressure detected by the pressure detection unit and an inclination of the fuel pressure after the inflection point appears, after an output of the drive command signal. A delay time computation unit computes a response delay time of the pressure adjusting valve with respect to the drive command signal for each of the first on-off valve and the second on-off valve based on the inflection point and the inclination acquired by the acquisition unit.

Various embodiments may include a method for adapting the opening behavior of a fuel injector having a solenoid drive, the method comprising: applying a voltage pulse having a predetermined electrical voltage to the solenoid drive; acquiring a time profile of the strength of a current flowing through the solenoid drive; comparing the acquired time profile with a reference profile; and adjusting a value of a mechanical parameter of the fuel injector to reduce a deviation between the acquired time profile of the strength of the current and the reference profile.