A fuel system is disclosed for use with an engine, including a fuel injector assembly fluidly coupled with a low-pressure fuel conduit, an accumulator, and a cap within an opening in the accumulator. The fuel injector assembly may be structured to draw in low-pressure fuel, pressurize the fuel, and store the pressurized fuel in the accumulator for injection to a combustion chamber. The cap has a pressure sensor and a pressure relief valve therein, and drains fuel leaked past fluid seals between the cap and each of the pressure sensor, the pressure relief valve, and the accumulator by way of a common drain line.

An energize-to-close solenoid operated spool type inlet control valve for a high pressure fuel pump is variably positionable relative to a sleeve having three inlet feed ports and the inlet check valve member, to implement three stages of pump operation: limp-home, low-pressure flow from the low-pressure feed pump to the common rail, no flow to the common rail, and metered quantity of flow to the common rail. The spool valve includes an axially extending internal passage fluidly connected to a fluid volume at the front end of the spool valve, and a control port at the back end of the spool valve, selectively alignable to fluidly connect the ports. Two springs of different lengths either alone or together, bias the spool valve toward opening of the inlet check valve.

A fuel system for an internal combustion engine includes a common rail and a plurality of fuel injectors connected to the common rail and each including an outlet check, an injection control valve, and an injection rate controller. The injection rate controller varies a flow area to a nozzle of the fuel injector such that a pressure drop through the fuel injector is varied to provide injection rate shaping.

A fuel system for an internal combustion engine includes a common rail and a plurality of fuel injectors connected to the common rail and each including an outlet check, an injection control valve, and an injection rate controller. The injection rate controller varies a flow area to a nozzle of the fuel injector such that a pressure drop through the fuel injector is varied to provide injection rate shaping.

A high pressure pump for complex injection engines is provided. A body of the high pressure pump includes a first flow path that transports the low pressure fuel flowing in through the low pressure fuel inlet and a low pressure fuel storage chamber that is disposed in a lower portion of the body to store the low pressure fuel transported from the first flow path. A second flow path transports the low pressure fuel stored in the low pressure fuel storage chamber and a flow control valve is disposed over the low pressure fuel storage chamber to discharge the low pressure fuel, transported through the second flow path, to the pressure unit or the damper disposed in an upper portion of the body based on an opening or closing operation. A low pressure fuel outlet discharges the low pressure fuel, transported through the damper, to a low pressure fuel rail.

An improved fuel injection pump is provided for an internal combustion engine (e.g., diesel engine), and is configured such that the secondary hand pump of the prior art can be eliminated. To achieve this result, the injection pump employs a one-way bearing or clutch on the input side of the drive shaft of the injection pump. By employing a one-way bearing or clutch, such as of the concentric roller type, or other suitable clutch, the fuel injection pump can be operated by direct coupling of the engine and the drive shaft of the fuel injection pump. Also with this configuration, once the engine is stopped, the drive shaft of the fuel injection pump can be manually driven in order to prime the system. Accordingly, by locating a one-way bearing or similar clutch device along the driveline of the fuel injection pump, the fuel injection pump can be both manually operated when the engine is shut off and automatically driven when the engine is running.

Disclosed is a method for controlling a fuel pump for a motor vehicle, including determining if a set amount of fuel to be compressed is less than the minimum volume that can be delivered by the pump and, if this is the case, determining a new set amount of fuel to be compressed equal to the product of a number of compressions of a volume equal to the set amount of fuel to be compressed required to achieve at least the minimum volume that can be delivered and the set amount of fuel to be compressed; transmitting the new set amount of fuel to be compressed to the fuel pump; and subsequently disabling the fuel pump for a number of occurrences of the set amount of fuel equal to the number of compressions of a volume equal to the set amount of fuel to be compressed.

[Problem] To provide, in an engine provided with two cylinder rows, a technology that, while suppressing a cost increase, can suppress a difference in combustion performance between the cylinder rows. [Solution] An exemplary engine includes: a first cylinder row having plural cylinders arranged in a front and rear direction; a second cylinder row arranged parallel to the first cylinder row; plural first injectors provided for the respective cylinders of the first cylinder row, plural second injectors provided for respective cylinders of the second cylinder row; and a fuel pump having a first discharge port to discharge a fuel to the plural first injectors and a second discharge port to discharge a fuel to the plural second injectors. The fuel pump is placed between the first cylinder row and the second cylinder row in a plan view from an up and down direction.

A method of determining fuel leak of fuel injectors of an injection system of a combustion engine, said method including determining a baseline pressure based on a predetermined integral response threshold and for each fuel injector determining a primary reference integral response by obtaining the associated primary reference integral response by obtaining the current integral response while running the engine at the baseline pressure with the respective fuel injector fluidly isolated.

The present disclosure relates to the field of electromechanics. The teachings may be applied to high-pressure valves, including methods for operating a valve and with devices which are used for activating the valves. Some embodiments include methods for operating a pressure reduction valve for an accumulator injection system, wherein the valve is driven, against a return spring, with an energizable coil and armature, between a closed position and an open position. The method may include: supplying the coil with a defined electrical signal to move the armature, sensing the current intensity profile over time, and determining a movement profile for the defined current signal, including an opening or closing time, based at least in part on the current intensity profile over time.