Assembly device and assembly method

An assembly device with a motor-driven screw device for the tightening or loosening of screws, with a screw head and a housing, wherein the screw device comprises:

• a first angle-measuring device for the detection of the rotation angle of the housing about the axis of the screw head relative to the surroundings;
• wherein the assembly device comprises a detection unit for the detection of erroneous sensor data in a rest state, comprising:
• means for detecting the rest state, and
• means for comparing sensor data measured in the rest state with one or more predefined threshold values.

A method for the tightening or loosening of screws by means of a motor-driven screw device with a screw head and a housing, the method comprising:

• detecting a rotation angle of the housing about an axis of the screw head relative to the surroundings of the housing by means of a first angle-measuring device;
• wherein detecting a rotation angle comprises:
• detecting erroneous sensor data in a rest state by means of a detection unit, comprising:
• detecting the rest state;
• and
• comparing, by comparison means, the sensor values measured in the rest state with predefined threshold values.