摘要:
Disclosed is a fuel injection device comprising a housing and a valve element disposed therein and cooperating with a valve seat located in the area of at least one fuel discharge port. The valve element is composed of several parts while at least two parts of the valve element are coupled to each other via a hydraulic coupler.
摘要:
A common rail injector having an injector housing having a fuel supply line which communicates with a central high-pressure fuel source outside the injector housing and with a pressure chamber inside the injector housing, from which pressure chamber, as a function of the position of a 3/2-way control valve, fuel subjected to high pressure is injected. The 3/2 way control valve, includes a valve piston, movable back and forth in the injector housing between a position of repose and an injection position, which piston is coupled hydraulically with a piezoelectric actuator that is subjected to the pressure from the high-pressure fuel source.
摘要:
An apparatus for injecting fuel into an internal combustion engine having a fuel injector acted on with highly pressurized fuel actuated by means of a metering valve device that is able to control the pressure in a pressure booster control chamber so that in a pressure booster pressure chamber delimited by a pressure booster piston which can be filled via a check valve with high-pressure fuel and communicates with an injection valve member pressure chamber, the pressure booster piston increases the pressure, causing an injection valve member for injecting fuel to open. To assure a correct injection quantity even if an abrupt pressure drop occurs in the high-pressure fuel source, the pressure booster piston is situated and designed so that if a pressure drop occurs in the high-pressure fuel source, then starting from its neutral position, the pressure booster piston has the capacity to execute a pressure compensation movement by means of which the pressure in the pressure booster pressure chamber is adapted to the pressure of the high-pressure fuel source.
摘要:
A fuel injector with a pressure booster supplied with fuel at high pressure. A work chamber of the pressure booster is separated from a differential pressure chamber via a booster piston. The pressure relief and the subjection to pressure of the differential pressure chamber are effected via a switching valve which communicates with the differential pressure chamber via a control line. A pressure chamber on an injection valve member communicates with a compression chamber of the pressure booster via a pressure chamber supply line. The switching valve is embodied as a direct-switching 3/2-way valve, whose valve needle is pressure-balanced and has both a sliding seat and a slide seal.
摘要:
A fuel injection device for an internal combustion engine, having two valve elements each having a hydraulic control surface acting in the closing direction and associated with a hydraulic control chamber. A control valve influences the pressure in the control chamber, and loading devices act on the valve elements in the opening direction. The valve elements react at different hydraulic opening pressures prevailing in the control chamber. The control valve is able to set at least three different pressure levels in the control chamber: all of the valve elements are closed at a comparatively high pressure level; one valve element is open at a medium pressure level; and all of the valve elements are open at a comparatively low pressure level.
摘要:
A fuel injection system for an internal combustion engine and having a high-pressure fuel pump and a fuel injection valve for each engine cylinder. A first electrically actuated control valve controls a connection of the pump working chamber to a low-pressure region and a second electrically actuated control valve controls a connection of a control pressure chamber of the fuel injection valve to a relief region. A pressure reservoir is filled by the high-pressure fuel pump and from which fuel can be withdrawn in order to execute a fuel injection with the fuel injection valve independent of the delivery from the high-pressure fuel pump. The connection between the fuel pump and the pressure reservoir and injection valve contains a coupling device having a piston acted on at one end by the pressure prevailing in the pressure reservoir acted on at the other end by the pressure prevailing in the connection. The piston executes a delivery stroke oriented toward the pressure chamber in order to execute a fuel injection, and that the coupling device contains a bypass connection via which the connection communicates with the pressure reservoir.
摘要:
A servo-valve for a fuel injector equipped with a pressure booster whose working chamber is separated from a differential pressure chamber by a booster piston in which an actuator can connect a control chamber to a first low-pressure return and the differential pressure chamber can be connected to a second low-pressure return or to a return system in which the returns are connected to each other. A first servo-valve piston has a first sealing seat, and a second piston, embodied as a sealing sleeve, is accommodated on the first servo-valve piston and, together with a valve housing, constitutes a second sealing seat. When the pressure in the control chamber is relieved, this second sealing seat is closed with a shorter stroke, sooner than the first sealing seat. When the control chamber is subjected to pressure, the second sealing seat opens only after the first sealing seat is closed.
摘要:
A fuel injector for injecting fuel into the combustion chamber of an internal combustion engine is equipped with a pressure booster that has a working chamber continuously connected to a common rail, and has a differential pressure chamber, which a piston part separates from the working chamber. The fuel injector also has an injection valve member. To actuate the fuel injector, a valve having a control valve in the form of a servo valve and an actuating valve that actuates this control valve. The multistage valve controls both the pressure booster and the injection valve member. The control valve and the actuating valve are hydraulically coupled to each other and different outlet throttles can be opened and closed in order to achieve different opening speeds of a servo valve piston.
摘要:
A fuel injection system for an internal combustion engine and having a high-pressure fuel pump and a fuel injection valve for each engine cylinder. A first electrically actuated control valve controls a connection of the pump working chamber to a low-pressure region and a second electrically actuated control valve controls a connection of a control pressure chamber of the fuel injection valve to a relief region. A pressure reservoir is filled by the high-pressure fuel pump and from which fuel can be withdrawn in order to execute a fuel injection with the fuel injection valve independent of the delivery from the high-pressure fuel pump. The connection between the fuel pump and the pressure reservoir and injection valve contains a coupling device having a piston acted on at one end by the pressure prevailing in the pressure reservoir acted on at the other end by the pressure prevailing in the connection. The piston executes a delivery stroke oriented toward the pressure chamber in order to execute a fuel injection, and that the coupling device contains a bypass connection via which the connection communicates with the pressure reservoir.
摘要:
A fuel injection apparatus for injecting fuel into the combustion chambers of an internal combustion engine. includes a high pressure accumulator, a pressure booster, and a metering valve. The pressure booster includes a working chamber and a control chamber that are separated from each other by an axially movable piston. A pressure change in the control chamber produces a pressure change in a compression chamber that acts on a nozzle chamber via a fuel inlet. The nozzle chamber encompasses a nozzle needle. A nozzle spring chamber that acts on the injection valve element can be filled on the high-pressure side via a line that leads from the compression chamber and contains an inlet throttle restriction. On the outlet side, the nozzle spring chamber is connected to a chamber of the pressure booster via a line that contains an outlet throttle restriction.