A high-pressure injection device for an internal combustion engine to which engine segment times are assigned, having a high-pressure pump, a rail connected to the high-pressure pump via a high-pressure fuel line, at least one injector, a digital pressure reduction valve connected to the rail, a fuel return line connected to the pressure reduction valve, and a control unit. The control unit is configured to switch the pressure reduction valve into the transmissive state only in predetermined engine segment times, and to maintain said transmissive state of the pressure reduction valve for a time period which is greater than the duration of one engine segment time.

The present invention relates to an apparatus (1) for pressure control in a fuel feed of an internal combustion engine with a common rail injection, comprising a housing (10) with an opening (15), and an electromagnetic high pressure valve (30), wherein the electromagnetic high pressure valve (30) is at least partially inserted into the opening (15) of the housing (10) at the end, wherein the electromagnetic high pressure valve (30) is connected in a pressure-tight manner in the opening (15) to the housing (10) by a connection (20) and the connection (20) has a first portion (21) and at least one second portion (22), and wherein the first portion (21) and the at least one second portion (22) have different mechanical and/or geometric properties.

The invention relates to a pressure regulator for a high-pressure ramp of a system for injecting fuel into an internal combustion engine, comprising a solenoid valve element (10) which receives an electromagnet (40). The electromagnet controls a needle (20) that closes a valve seat (30) which is connected to a high-pressure inlet and opens into a discharge chamber (13), said discharge chamber communicating with a liquid recirculation system (5) by means of outlet openings (14). The rear face (12) of the solenoid valve element (10) receives a coil (40) which controls the opening process of an armature (41) that is rigidly connected to the needle (20) and is subject to a closing return spring (25). The discharge chamber (13) is located on the front face (11) of the solenoid valve element (10) on the axis (XX) of the needle (20), and the discharge chamber surrounds the needle. A cavity (15) passes through the discharge chamber, said cavity receiving an inlet valve element (50), and a bore (51) which opens into the valve seat (30) passes axially through the inlet valve element. The discharge chamber (13) through which the needle (20) passes axially and the outlet openings (14) which are connected to the liquid recirculation system open transversally into a wall (131) in the discharge chamber (13) .sub.in below the upper part (132) of the chamber. The regulator is characterized that the regulator comprises an annular expansion (70) of the discharge chamber (13) below the outlet openings (14) along the extension of a conical surface (31), which forms the valve seat (30) and an annular dead volume (70), above the surface (54) of the valve element (50), which forms the base of the discharge chamber (13) and has the valve seat (30) in the center of the valve element.

A method and system for controlling a fuel pressure valve of a vehicle are disclosed. The disclosed control method includes engine start entrance for controlling a controller to increase an allowable deviation between a current target fuel pressure and an actual fuel pressure when an ignition switch-on signal is received by the controller, fuel pressure determination for controlling the controller to determine whether a deviation value between the target fuel pressure and an actual fuel pressure measured by a sensor is greater than an allowable deviation, and valve control for controlling the controller to determine a duty value for control of opening of the fuel pressure valve, and then controlling the controller to open the fuel pressure valve using the determined duty value, thereby decreasing the actual fuel pressure.

A fuel pump includes a camshaft that rotates in accordance with operation of an engine and a tappet provided in contact the camshaft. An ECU includes an angle determination unit configured to determine whether a rotation angle from a start of rotation of the camshaft when starting the engine is under a predetermined angle required for forming an oil film on a sliding portion of the tappet, and a control unit configured to, when the rotation angle from the start of rotation of the camshaft is determined to be under the predetermined angle, execute a limit process including at least one of limiting a fuel discharge pressure of the fuel pump or limiting a rotation of the camshaft.

A solenoid valve which regulates the pressure in a pressurized fuel injection system includes a body containing a needle that is pressed by an electromagnet including a coil and a magnetic core. The core has a cavity that is in fluid communication via an internal channel with a counterbore in the body into which the needle protrudes and into which fuel flows during use. The core also has a restriction which restricts the fluid communication and which attenuates pressure waves propagating in the fuel to prevent the waves from moving the core.

Methods and systems are provided for adjusting operation of fuel injectors of an internal combustion engine to reduce injector ticking noise during direct injection fuel rail pressure release. The method includes first reducing a significant part of the direct injection fuel rail pressure via a mechanical high pressure pump relief valve and only if further pressure relief is required then intermittently activating the direct injector to inject in small amount of fuel. Due to the reduced frequency of activation and small pulse-widths, the impact force transmitted from injectors to cylinder head is small thereby reducing the objectionable ticking noise.

A method for testing a high-pressure pump, particularly a high-pressure pump which is provided to inject fuel into a combustion engine, the method including filling the high-pressure pump with a fluid prior to switching it on.

A method for operating an internal combustion engine having an injection system which has a high-pressure accumulator, high pressure in the high-pressure accumulator being controlled via a suction throttle on the low-pressure side, acting as a first pressure control element in a first high-pressure control loop. During normal operation, a high-pressure disturbance variable is produced by a pressure regulating valve on the high-pressure side, acting as an additional pressure control element, via which fuel is re-directed from the high-pressure accumulator into a fuel reservoir, the at least one pressure regulating valve being controlled, during normal operation, based on a set volumetric flow rate for the fuel to be re-directed. A temporal development of the set volumetric rate is sensed and the set volumetric flow rate is filtered, a time constant for the filtering of the set volumetric flow rate being selected as a function of the sensed temporal development.

A method for operating an injection system of an internal combustion engine, including: providing the injection system includes a high pressure accumulator; regulating a high pressure in the high pressure accumulator in a normal operation by way actuating a low pressure-side suction throttle; regulating the high pressure in a first operating mode of safety operation by way of actuating at least one high pressure-side pressure control valve; carrying out a switchover from the normal operation into the first operating mode of safety operation if the high pressure reaches or exceeds a first limit pressure value; and carrying out a switchover from the first operating mode of safety operation into the normal operation if, starting from above a setpoint pressure value, the high pressure reaches or undershoots the setpoint pressure value, which is lower than the first limit pressure value.