Abstract: The opening and closing motion of a control piston effectively connected to an injection valve element is optimally designed in that in addition to a first control space, there is a second control space whose volume and fuel control pressure can be changed by the piston motion. During the opening motion, the pressure in the second control space retards the opening procedure. During the closing motion, the control piston is additionally accelerated by the system pressure when there is a predetermined pressure in the second control space in order to effect rapid closing of the injection openings. Relief elements ensure a pressure balance between the second control space and the high-pressure region. One of the two control spaces is connected to the high-pressure region when there is a predetermined pressure in the second control space.

Abstract: The opening and closing motion of a control piston effectively connected to an injection valve element is optimally designed in that in addition to a first control space, there is a second control space whose volume and fuel control pressure can be changed by the piston motion. During the opening motion, the pressure in the second control space retards the opening procedure. During the closing motion, the control piston is additionally accelerated by the system pressure when there is a predetermined pressure in the second control space in order to effect rapid closing of the injection openings. Relief elements ensure a pressure balance between the second control space and the high-pressure region. One of the two control spaces is connected to the high-pressure region when there is a predetermined pressure in the second control space.

Abstract: A fuel injection valve for intermittent fuel injection into a combustion space of a combustion engine comprises an injection valve indirectly actuated electromagnetically by a hydraulic amplifier. The opening motion of the injection valve element remains limited at low and medium injection pressure, while the opening motion of the injection valve element is substantially more rapid and the opening path of the injection valve element substantially larger at high injection pressure than it is at low to medium injection pressure. It is possible to operate the engine over the complete load and rotational speed range under optimum injection conditions.

Abstract: A fuel injection valve for intermittent fuel injection into a combustion space of a combustion engine comprises an injection valve indirectly actuated electromagnetically by a hydraulic amplifier. The opening motion of the injection valve element remains limited at low and medium injection pressure, while the opening motion of the injection valve element is substantially more rapid and the opening path of the injection valve element substantially larger at high injection pressure than it is at low to medium injection pressure. It is possible to operate the engine over the complete load and rotational speed range under optimum injection conditions.

Abstract: The injector 10 for intermittently injecting fuel under high pressure in an internal combustion engine is provided with an injector valve member (18). The movement of this injector valve member (18) to open and close a fuel discharge orifice (24) is controlled by the fuel pressure in a control chamber (40) acting on a valve piston (26) on the side opposite to the discharge orifice (24). A cylindrical member (36) surrounds the upper part (30) of the valve piston (26). Energization of a solenoid (44) results in the opening of a pilot valve (46) and a subsequent quick drop of the fuel pressure in the control chamber (40). The solenoid (44) in addition to its function as a high speed actuator for the pilot valve (46) is also used to carry and transmit the force resulting from the fuel pressure in the control chamber (40) and acting on the cylindrical member (36), on the solenoid (44) and on further members (48, 50, 52, 14).

Abstract: The fuel injectors (4) of an internal combustion engine (2) are connected to a pump (10) by means of fuel supply lines (12) which open into the high-pressure part (34) of the injectors (4). The cross-sectional area of the fuel connection (12, 34) between the pump (10) and the injection orifices of the injectors (4) is substantially bigger than the total cross-sectional area of all of the injection orifices of an injector (4). An unrestricted flow path for the pressurized fuel is provided between the pump (10) and the area immediately upstream of the injection orifices. Due to the small pressurized volume of the system, the transient behaviour of the injection system is fast and can easily be matched to the needs of a particular engine application.

Abstract: The movement of an injector valve member (52) which closes and temporarily opens discharge orifices (58) communicating with the combustion chamber of an internal combustion engine is controlled by the fuel pressure in a control chamber (72) and by a difference in the pressure forces acting on a piston (60) having two sections (63, 69) with different diameters arranged at one end of the valve member (52). The pressure in the control chamber (72) to control the movement of the valve member (52) is controlled by means of two axially aligned orifices (67, 70) and by a solenoid valve (S) for closing and temporarily opening one of said orifices (70). A member (71) and the top end of the thicker section (69) of the piston (60) define said control chamber (72). Said thicker section (69) guides said member (71) at its inside, while the latter is not guided on its circumference (71b). The thinner section (63) of piston (60) is guided in the injector housing (44).