초록 ▼

The invention relates to a 3/2-way valve for controlling the injection of fuel in a common rail injection system of an internal combustion engine, having a first switching position, in which an injection nozzle is in communication with a fuel return, and having a second switching position, in which

The invention relates to a 3/2-way valve for controlling the injection of fuel in a common rail injection system of an internal combustion engine, having a first switching position, in which an injection nozzle is in communication with a fuel return, and having a second switching position, in which the injection nozzle is in communication with a high-pressure fuel reservoir. To improve the function and quality of the injection, the 3/2-way valve includes a force-balanced control piston, and the control edge of the control piston is pressure-equalized by means of a blind bore.

대표청구항 ▼

1. A 3/2-way valve for controlling the injection of fuel in a common rail injection system of an internal combustion engine, having a control piston (44) guided in a housing (53), in which the control piston (44), in a first switching position, opens a hydraulic connection between an injector (7) an

1. A 3/2-way valve for controlling the injection of fuel in a common rail injection system of an internal combustion engine, having a control piston (44) guided in a housing (53), in which the control piston (44), in a first switching position, opens a hydraulic connection between an injector (7) and a fuel return (42), and in a second switching position the control piston (44) opens a hydraulic connection between the injector (7) and a high-pressure fuel reservoir (3), and means for force balancing the control piston (44, 70), wherein the control piston (44, 70) has two guides, with a larger guide diameter and a smaller guide diameter; wherein the control piston (44, 70) has a control edge cooperating with the smaller guide diameter; wherein a blind bore (50, 62) is embodied in the end, remote from the control edge, of the control piston (44, 70); wherein the blind bore (50, 62) can be subjected to pressure via a bore (51); and wherein a throttle is provided in the bore (51).2. The 3/2-way valve claim 1, further comprising an additional piston (52) guided in the blind bore (50, 62).3. The 3/2-way valve of claim 2, further comprising a circumferential groove (73) embodied on the control piston (70), the groove (73), in the assembled state of the 3/2-way valve, being disposed in the region of at least one fuel return opening (68).4. The 3/2-way valve of claim 2, wherein the control piston (44, 70) comprises a valve seat (46) whose diameter is equivalent to the larger guide diameter.5. The 3/2-way valve of claim 2, wherein the control piston (44, 70) is prestressed by a closing spring (45).6. The 3/2-way valve of claim 2, wherein the control piston (44, 70) is actuated via a piezoelectric actuator.7. The 3/2-way valve of claim 1, further comprising a circumferential groove (73) embodied on the control piston (70), the groove (73), in the assembled state of the 3/2-way valve, being disposed in the region of at least one fuel return opening (68).8. The 3/2-way valve of claim 7, wherein the control piston (44, 70) comprises a valve seat (46) whose diameter is equivalent to the larger guide diameter.9. The 3/2-way valve of claim 7, wherein the control piston (44, 70) is prestressed by a closing spring (45).10. The 3/2-way valve of claim 7, wherein the control piston (44, 70) is actuated via a piezoelectric actuator.11. The 3/2-way valve of claim 1, wherein the control piston (44, 70) comprises a valve seat (46) whose diameter is equivalent to the larger guide diameter.12. The 3/2-way valve of claim 11, wherein the control piston (44, 70) is prestressed by a closing spring (45).13. The 3/2-way valve of claim 1, wherein the control piston (44, 70) is prestressed by a closing spring (45).14. The 3/2-way valve of claim 1, wherein the control piston (44, 70) is actuated via a piezoelectric actuator.15. The 3/2-way valve of claim 1, combination with an injection nozzle or a nozzle holder.