Rotation rate controlled vacuum nozzle brush

The vacuum nozzle of the invention consists of a housing which is open at the floor side and in which a brush roller which is provided with brushes and can be driven by an electric motor is arranged. The speed of revolution of the brush roller can be controlled as a function of different suction parameters, the speed of revolution of the brush roller being detected indirectly or directly by at least one sensor and the signal of the sensor being converted in an electronic evaluation unit. This evaluation unit in turn supplies a control variable for the electric motor which drives the brush roller. In order to reduce the sensitivity to contamination of the sensing of the speed of revolution and thus of the control system, the sensor consists of an electro-acoustic sensor which is arranged in the region of at least one source, in particular in the region of the brush roller, which emits a noise which is dependent on the speed of revolution and/or load, in or on the housing of the vacuum nozzle.