| 摘要 |
The invention relates to a fuel injector for internal combustion engines for injecting fuel at high pressure, comprising a pressure chamber formed in an injector body, in which pressure chamber a nozzle needle is arranged in a longitudinally movable manner, which nozzle needle has a cone region tapered in a combustion chamber direction and a pin region having a constant diameter d23 at a combustion-chamber end of the nozzle needle. The injector body has a substantially conical nozzle needle seat, from which a first injection opening extends, and a blind hole, which adjoins the nozzle needle seat on the combustion chamber side. The blind hole has a cylindrical segment, which has the diameter d31, and a hole base, from which a second injection opening extends. The cone region of the nozzle needle interacts with the nozzle needle seat and thereby opens and closes the first injection opening and the second injection opening with respect to the pressure chamber. During a partial stroke of the nozzle needle, the first injection opening and the second injection opening are connected to each other by means of a throttle gap, which is formed in the blind hole between the pin region and the wall of the blind hole, and the throttle gap remains constant at least over the partial stroke of the nozzle needle. |
| 主权项 |
1. A fuel injector (100) for internal combustion engines for injecting fuel at high pressure, the fuel injector comprising a pressure chamber (30), which is formed in an injector body (10) and in which a nozzle needle (20) is arranged in a longitudinally movable manner, which nozzle needle has, at a combustion-chamber end thereof, a cone region (22), which is tapered in a combustion chamber direction, and also has a pin region (23) of constant diameter (d23), wherein the injector body (10) has a substantially conical nozzle needle seat (17), from which a first injection opening (1) extends, and a blind hole (31), which adjoins the nozzle needle seat (17) at the combustion-chamber end and has a cylindrical segment having the diameter (d31) and a hole base, from which a second injection opening (2) extends, wherein the cone region (22) of the nozzle needle (20) interacts with the nozzle needle seat (17) and thereby opens and closes the first injection opening (1) and the second injection opening (2) with respect to the pressure chamber (30),
characterized in that, at least during a partial stroke (s) of the nozzle needle (20), the first injection opening (1) and the second injection opening (2) are connected to one another via a throttle gap (32), which is formed in the blind hole (31) between the pin region (23) and a wall of the blind hole (31), and the throttle gap (32) remains constant at least over the partial stroke (s) of the nozzle needle (20). |
