The hydraulic injection system (100) with cam comprises an injection valve (50) housed in a tubular injection nozzle (54), a gap being formed between a valve stem (51) of said valve (50) and the inner surface of the tubular injection nozzle (54) to allow an injectable fluid (58) coming from pressurizing means (10) to flow, while a receiver piston (62) fixed with respect to said valve (50) receives on the one hand the pressure of the injectable fluid (58) to hold said valve (50) closed, and on the other hand, the pressure of a hydraulic fluid (60) to open said valve (50), an injection cam (67) being capable to move said receiver piston (62) via an emitter piston (69) and said hydraulic fluid (60).

A method for operating a fuel injection system for a vehicle is provided. In particular, the fuel injection system includes an injection nozzle having a nozzle body, a nozzle orifice and a nozzle needle movable in the nozzle body. The method including: measuring an actual injection timing of the injection nozzle during injection based on an electrical signal generated by the nozzle needle through an electric contact with the nozzle body so that the electrical signal identifies an open state and a closed state of the injection nozzle; calculating a deviation of the actual injection timing from a scheduled injection timing of the fuel injection system; and controlling the injection nozzle by adjusting injection parameters of the injection nozzle based on the evaluated deviation.

The subject matter of this specification can be embodied in, among other things, an apparatus that includes a high-pressure pump having a pump element, a regulating device positioned upstream of the high-pressure pump, a fuel channel defined between an inflow side of the regulating device and the pump element, and a safety device, actuatable to reduce a through-flowable cross section of the fuel channel.

The pressing part includes an abutment part capable of being in contact with the inner peripheral surface of the pressing passage, and a depressed opposite part that is opposed to the exhaust port at a position away from the exhaust port in a perpendicular direction perpendicular to the displacement direction due to an outer peripheral surface of the pressing part recessed from the abutment part even when the abutment part is in contact with the inner peripheral surface of the pressing passage. When the abutment part is in contact with the inner peripheral surface of the pressing passage, a depression dimension of the depressed opposite part relative to the abutment part is set, such that an amount of fuel discharged from the valve chest is defined by the exhaust throttle part instead of a gap between the depressed opposite part and the inner peripheral surface of the pressing passage.

A fuel injection device includes a first driver for driving a first valve and a second driver for driving a second valve. A control device performs an open control of the first valve multiple times by using the first driver, for enabling multistage fuel injection from an injection hole in one fuel cycle of an internal combustion engine via a high pressure fuel passage. The control device performs an open-close control of the second valve by using the second driver during an open control of the first valve by using the first driver, for controlling an inclination of injection rate of the fuel injection. The control device stops an output of a drive signal to the second driver when detecting an overheat of a drive circuit based on a temperature detection result of a temperature sensor.

The invention relates to a fuel injector arrangement (1) comprising a number of fluid supply paths (29, 31, 39), namely, a first (29), a second (31) and a third fluid supply path (39). The fuel injector arrangement (1) has a first switching device (43) in the second fluid supply path (31). Said first switching device, controlled by the fluid pressure in the third fluid supply path (39), opens or blocks the second fluid supply path (31). The fuel injector arrangement (1) has a second switching device (49) in the first fluid supply path (29). Said second switching device, controlled by the fluid pressure downstream of the first switching device (43) in the second fluid supply path (31), opens or blocks the first fluid supply path (29).

A fuel injection device includes a first driver for driving a first valve and a second driver for driving a second valve. A control device performs an open control of the first valve multiple times by using the first driver, for enabling multistage fuel injection from an injection hole in one fuel cycle of an internal combustion engine via a high pressure fuel passage. The control device performs an open-close control of the second valve by using the second driver during an open control of the first valve by using the first driver, for controlling an inclination of injection rate of the fuel injection. The control device stops an output of a drive signal to the second driver when detecting an overheat of a drive circuit based on a temperature detection result of a temperature sensor.

A method for operating a fuel injection system for a vehicle is provided. In particular, the fuel injection system includes an injection nozzle having a nozzle body, a nozzle orifice and a nozzle needle movable in the nozzle body. The method including: measuring an actual injection timing of the injection nozzle during injection based on an electrical signal generated by the nozzle needle through an electric contact with the nozzle body so that the electrical signal identifies an open state and a closed state of the injection nozzle; calculating a deviation of the actual injection timing from a scheduled injection timing of the fuel injection system; and controlling the injection nozzle by adjusting injection parameters of the injection nozzle based on the evaluated deviation.

The invention relates to a fuel injector arrangement (1) comprising a number of fluid supply paths (29, 31, 39), namely, a first (29), a second (31) and a third fluid supply path (39). The fuel injector arrangement (1) has a first switching device (43) in the second fluid supply path (31). Said first switching device, controlled by the fluid pressure in the third fluid supply path (39), opens or blocks the second fluid supply path (31). The fuel injector arrangement (1) has a second switching device (49) in the first fluid supply path (29). Said second switching device, controlled by the fluid pressure downstream of the first switching device (43) in the second fluid supply path (31), opens or blocks the first fluid supply path (29).

Various methods and systems are provided for a pressure relief valve of a fuel system. In one example, a valve includes a first chamber in fluid communication with a first fuel line, a second chamber in fluid communication with a second fuel line and in fluid communication with a fuel storage tank, a piston separating the first chamber from the second chamber, and a needle coupled to the piston and controlling a flow passage between the second fuel line and the second chamber, where the piston and needle are sized such that a force applied on the piston by the first chamber parallel to an axis of movement of the piston maintains the needle in a closed position when the first fuel line flows fuel at a first pressure and the second fuel line flows fuel at a second pressure, the second pressure greater than the first pressure.