| 摘要 |
The invention relates to a hydraulic system for an automatic gearbox, more particularly a dual-clutch gearbox, for a motor vehicle, comprising a high-pressure circuit (H) which includes a pressure accumulator (25), at least one clutch (K1, K2) and actuators (22), and comprising a low-pressure circuit (N) for cooling the clutch (K1, K2), the high-pressure circuit (H) and the low-pressure circuit (N) each containing a hydraulic cooling pump (59) and a hydraulic charging pump (53) that can be driven by a shared electric motor (57); and comprising a controller (39) which, when it is detected that the pressure accumulator needs to be charged, controls the electric motor (57) to run at a charging setpoint speed (nsoll,laden), and/or, when it is detected that cooling is needed or another need exists, controls the electric motor (57) to run at a cooling setpoint speed or another setpoint speed (nsoll,kühlen). According to the invention, the electric motor (57) is paired with a current measuring device (75) for measuring an actual current consumption (Iist) and a rotational speed sensor (77) for measuring an actual rotational speed (nist). The controller (39) has an analysis unit (73) which uses the actual current consumption (list) and the actual rotational speed (nist), specifically from the comparison of the actual current consumption (Iist) with a reference value (Iref), to detect a need for charging of the pressure accumulator. |
