A method for operating a fuel injection system with pressure reduction, and a fuel injection system that includes a fuel injection valve with a servo valve are provided. The method for operating a fuel injection system includes performing a desired pressure reduction in the pressure accumulator using at least one fuel injection valve of the fuel injection system. This is achieved by opening a servo valve in the fuel injection valve, which is opened, during a pressure reduction phase, just wide enough that the actual closing element remains closed and as a result no fuel injection process takes place.

A method and an assembly for controlling the pressure in a high-pressure region of an injection system in an internal combustion engine. A set high pressure is compared to an actual high pressure in order to determine a control deviation, the control deviation representing an input variable of a controller. A high pressure pump is controlled by a solenoid valve and the angle at which the delivery of fuel by the at least one high-pressure pump is to start is used as a manipulated variable of the high-pressure closed-loop control system.

An apparatus includes an input module structured to interpret a fuel pressure command indicative of a target fuel pressure within an accumulator and a target fuel injection characteristic, a pump module structured to control a pump assembly to provide fuel to the accumulator to maintain the target fuel pressure within the accumulator, an injector module structured to control a plurality of fuel injectors to inject fuel into an engine based on the target fuel injection characteristic, a pressure module structured to interpret pressure data regarding an actual fuel pressure within the accumulator and to determine a pressure difference between the target fuel pressure and the actual fuel pressure, and a modulation module structured to determine a final fuel injection command responsive to the pressure difference exceeding a first magnitude threshold where the final fuel injection command is based on the pressure difference and the target fuel injection characteristic.

A fuel pressure control device determines whether it is during a descending period of a plunger descending or an ascending period of the plunger ascending, and puts a first drive mechanism and a second drive mechanism in an energized state during the descending period and in a non-energized state during the ascending period, when there is a pressure reduction request to lower a fuel pressure in a high-pressure passage.

A valve assembly for a fuel pump is disclosed. In certain aspect, the valve assembly includes a housing defining a valve chamber, a valve inlet in fluid communication with the valve chamber, a valve outlet in fluid communication with the valve chamber, a valve seat; a valve body movably disposed within the valve chamber, a retainer sealingly engaging the housing and defining a cavity between the base portion of the valve body and the retainer, wherein the retainer comprises one or more control orifices formed therein and configured to provide fluid communication to the cavity to regulate a position of the valve body based on at least a pressure difference between the valve chamber and the cavity, and a spring member disposed between the retainer and the valve body, wherein the spring member is configured to bias the valve body.

A high pressure container arrangement includes a reservoir having an outer wall and an over pressure relief orifice through which high pressure fluid may flow when the fluid pressure inside the reservoir exceeds a predetermined pressure threshold. The high pressure container arrangement also includes a pressure limiting valve having a housing in which is arranged a closing member permanently biased by a spring toward a closed position and, when the pressure in the reservoir exceeds the predetermined threshold the closing member is pushed in an open position. The housing of the pressure limiting valve is integral to the wall of the reservoir.

An apparatus includes an input module structured to interpret a fuel pressure command indicative of a target fuel pressure within an accumulator and a target fuel injection characteristic, a pump module structured to control a pump assembly to provide fuel to the accumulator to maintain the target fuel pressure within the accumulator, an injector module structured to control a plurality of fuel injectors to inject fuel into an engine based on the target fuel injection characteristic, a pressure module structured to interpret pressure data regarding an actual fuel pressure within the accumulator and to determine a pressure difference between the target fuel pressure and the actual fuel pressure, and a modulation module structured to determine a final fuel injection command responsive to the pressure difference exceeding a first magnitude threshold where the final fuel injection command is based on the pressure difference and the target fuel injection characteristic.

A method for operating an internal combustion engine having an injection system which has a high-pressure accumulator, wherein a high pressure in the high-pressure accumulator is regulated via a suction throttle on the low-pressure side as a first pressure control member in a first high-pressure control loop, wherein in a normal operation a high-pressure disturbance variable is produced via a pressure control valve on the high-pressure side as a second pressure control member, via which fuel is redirected from the high-pressure accumulator to a fuel reservoir. For this purpose, the high pressure in a safety operation is regulated by the pressure control valve via a second high pressure control loop, or, in the safety operation, a maximum fuel volume flow is continuously redirected from the high pressure accumulator to the fuel reservoir via the pressure control valve.

A system and method is provided to analyze an intermediate pressure signal portion between an end of an injection event signal portion and a start of a subsequent injection event signal portion. The analysis is simplified by identifying a plurality of single cycle windows and calculating a single value, such as a mean or a median, for each of the windows. An intermediate portion single value is determined by averaging the single values for each of the windows. The intermediate portion single value may then be used to identify pumping events or leakage errors that occur during the intermediate pressure signal portion that affect further analysis of the intermediate pressure signal portion.

A valve assembly for a fuel pump is disclosed. In certain aspect, the valve assembly includes a housing defining a valve chamber, a valve inlet in fluid communication with the valve chamber, a valve outlet in fluid communication with the valve chamber, a valve seat; a valve body movably disposed within the valve chamber, a retainer sealingly engaging the housing and defining a cavity between the base portion of the valve body and the retainer, wherein the retainer comprises one or more control orifices formed therein and configured to provide fluid communication to the cavity to regulate a position of the valve body based on at least a pressure difference between the valve chamber and the cavity, and a spring member disposed between the retainer and the valve body, wherein the spring member is configured to bias the valve body.