An injector apparatus (110) for injecting fluid under pressure into an associated chamber (132), the apparatus including a body (112), a first piston (114) moveable in the body, the first piston defining a first working area facing an associated chamber (132), a high pressure piston (18,118) defining a high pressure working area facing a high pressure chamber (19), the first working area being greater than the high pressure working area, the first piston (114) being operable to compress fluid in the high pressure chamber using the high pressure piston (118), the injector apparatus (110) having a first configuration having a first ratio of the first working area to high pressure working area and having a second configuration having a second ratio of the first working area to the high pressure working area, wherein a first ratio is different from the second ratio.

A fuel injector having a seat plate with a passage throttle; a valve insert arranged at a first side of the seat plate; a valve guide surrounding the valve insert and adapted for slidable reception of the valve insert; a spring sheath surrounding at least a section of a jet needle arranged at a second side of the valve insert, the second side opposite the first side and the seat plate; a valve chamber fluidly connected to the passage throttle; a control chamber adapted for reception of fuel; and a line arranged in the valve insert connecting the control chamber and the valve chamber to one another, wherein the line is closeable by placement of the valve insert onto the spring sheath.

An insert for use with a fuel injector comprises a shaft including a substantially cylindrical configuration defining a shaft cylindrical axis, a shaft radial direction, and a shaft diameter; and a head including a substantially cylindrical configuration defining a head cylindrical axis, a head radial direction, and a head diameter. The shaft and head may be attached to each other, the shaft cylindrical axis and the head cylindrical axis may be parallel to each other, the head diameter may be greater than the shaft diameter, and the shaft cylindrical axis may be spaced away from the head cylindrical axis.

A fuel injector includes an injector body comprising an internal injector cavity, a flow passageway, and a drain conduit. The flow passageway is in fluid communication with at least one injector orifice. The fuel injector further includes a valve assembly comprising a valve seat and a valve member in fluid communication with the fuel circuit. The valve member is configured to move between an open position allowing fuel flow through the at least one injector orifice and a closed position inhibiting fuel flow through the at least one injector orifice. The fuel injector also includes a nozzle valve element fluidly coupled to the valve assembly, an actuator operably coupled to the valve assembly and the nozzle valve element, and a flexible member configured to elastically deform in response to pressure in the fuel injector. The flexible member is configured to inhibit flow to the drain circuit during an injection event.

A fuel injector includes an injector body comprising an internal injector cavity, a flow passageway, and a drain conduit. The flow passageway is in fluid communication with at least one injector orifice. The fuel injector further includes a valve assembly comprising a valve seat and a valve member in fluid communication with the fuel circuit. The valve member is configured to move between an open position allowing fuel flow through the at least one injector orifice and a closed position inhibiting fuel flow through the at least one injector orifice. The fuel injector also includes a nozzle valve element fluidly coupled to the valve assembly, an actuator operably coupled to the valve assembly and the nozzle valve element, and a flexible member configured to elastically deform in response to pressure in the fuel injector. The flexible member is configured to inhibit flow to the drain circuit during an injection event.

A fuel injection system of an internal combustion engine includes: an injector having a hydraulic control chamber controlling the delivery of fuel through the injector, an actively controlled first valve system controlling the pressure relief from the control chamber, movable between: a first position in which the first valve system closes the injector by deterring the pressure from being relieved from the control chamber through the first relief circuit, and a second position in which the first valve system opens the injector by allowing the pressure to be relieved from the control chamber through the first relief circuit. A second relief circuit allows the pressure to be relieved from the control chamber through the second relief circuit. The second relief circuit includes a second valve system passively controlled by the fuel pressure and movable between two positions deterring or allowing the pressure to be relieved from the control chamber through the second relief circuit.

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.

Exemplary fuel injectors for use in fuel injection devices are disclosed. An injector may have a control chamber, which can be selectively relieved of pressure by means of a pilot valve in order to control a nozzle needle stroke of an axially displaceable nozzle needle of the injector. The fuel injector may have at least one nozzle on a first end, and the control chamber on a second end of the nozzle needle. The control chamber may be sub-divided by a throttle plate accommodated therein into a first chamber and a second chamber, with the second chamber being positioned closer to the nozzle, and the two chambers communicating with each other via the throttle plate. First and second resilient elements may be accommodated in a pre-stressed manner against the throttle plate in the first chamber and in the second chamber, respectively.

The invention relates to a fuel injection valve for the intermittent injection of fuel into the combustion chamber of an internal combustion engine having a housing which has a high pressure chamber and a low pressure chamber. In addition, the fuel injection valve has a control chamber which is divided by means of a control valve into a first and a second control chamber. The control valve in turn has a valve guide and a valve insert, wherein an outflow throttle which connects the first control chamber to the second control chamber is arranged in the valve guide. According to the invention, the connection which is formed by way of the outflow throttle between the first control chamber and the second control chamber can be interrupted temporarily in a targeted manner.

A fuel injector having a seat plate with a passage throttle; a valve insert arranged at a first side of the seat plate; a valve guide surrounding the valve insert and adapted for slidable reception of the valve insert; a spring sheath surrounding at least a section of a jet needle arranged at a second side of the valve insert, the second side opposite the first side and the seat plate; a valve chamber fluidly connected to the passage throttle; a control chamber adapted for reception of fuel; and a line arranged in the valve insert connecting the control chamber and the valve chamber to one another, wherein the line is closeable by placement of the valve insert onto the spring sheath.