| 摘要 |
A valve for metering fluid is specified, which valve has an electromagnet (15) for the actuation of a valve needle (13) which controls a metering opening (12). The electromagnet (15), when energized, generates a magnetic flux which runs via an outer pole (21), a hollow cylindrical inner pole (22), an armature (23) which is displaceable on an armature guide region (132) formed on the valve needle (13), and a working air gap (24) which is delimited by the armature (23) and the inner pole (22). On the valve needle (13) there is fixedly arranged a driver (25) which protrudes in axially displaceable fashion into a driver guide region (221) formed in the inner pole (22) and which has a radial abutment shoulder (251) for the armature (23), which abutment shoulder delimits a free travel or prestroke travel (26) of the armature (23), said free travel or prestroke travel being smaller than the axial gap width of the working air gap (24). To improve the noise characteristics of the valve, the driver (25) is enhanced so as to form an additional inner pole with a pole surface formed by the abutment shoulder (251), and for this purpose, the driver (25) is of magnetically conductive form, and a magnetic flux between armature (23) and valve needle (13) is prevented by means of a magnetically non-conductive material. |
