Pump device for creating low pressure in brake system of motor vehicle, has rotational speed detector detecting rotational speed of drive device during operation of pump device, and evaluation unit evaluating detected rotational speed

摘要

The pump device (1) has a pumping chamber (2) with a stator, a fluid inlet (3) and a fluid outlet (4). An electrical drive device (5) with a driven shaft (6) extends into an interior of the chamber. A rotor is attached at the shaft and rotated regarding the stator. A hall-sensor (10) detects operating current and/or operation voltage of the drive device. A pump device rotational speed detector e.g. optical electronic rotational speed detector, detects rotational speed of the drive device during operation of the pump device. An evaluation unit (9) evaluates the detected rotational speed.