| 摘要 |
The invention relates to a method for operating a feed pump (54, 59), which can be actuated by means of an electric motor (57), in a hydraulic circuit (N, H), which, in the case of a normal supply of fluid, sucks in the fluid from a fluid sump (55) into which the fluid which is circulated in the hydraulic circuit (N, H) can be fed back, and which at least partially sucks in air the case of an undersupply of fluid, wherein the electric motor (57) is integrated into a control circuit (R) which has a control unit (39) which actuates the electric motor (57) with an actuation rotational speed (nactuate) on the basis of an actual rotational speed (nact) and a setpoint rotational speed (nsetp). According to the invention, an evaluation unit (79) for detecting the undersupply of fluid is assigned to the control unit (39). The evaluation unit (79) compares the actual rotational speed (nact) with a reference rotational speed (nmax, N), specifically in the case of respectively identical current drain (Imax). On the basis of the comparison, the evaluation unit (79) determines whether an undersupply of fluid is present. |
