Position-measuring device and method for operating a position-measuring device

A method for operating a position-measuring device, the method comprising:

• providing the position-measuring device comprising:
• a graduation carrier which carries a measuring graduation and is non-rotatably connected to a shaft;
• a scanner which generates scanning signals by scanning the measuring graduation;
• evaluation electronics which process the scanning signals into a digital angle value of the shaft;
• and
• an interface which communicates with subsequent electronics, and
• mounting the scanner on a machine part that is supported so as to be movable in an axial direction of the shaft, so that the scanning signals are dependent on the position of the machine part in the axial direction of the shaft, and so that a measure of the position of the machine part in the axial direction of the shaft is determined from the scanning signals in the evaluation electronics.

A braking system for an electric motor, the braking system comprising:

• a brake disk non-rotatably connected to a shaft of the electric motor;
• an armature plate which is supported so as to be movable in the axial direction of the shaft;
• a first force-generator configured to produce a first force with which, in order to activate the brake, the armature plate is movable in the axial direction of the shaft and a surface of the armature plate is pressable against a surface of the brake disk to cause friction;
• a second force-generator configured to produce a second force with which the armature plate is pullable away from the brake disk in order to release the brake;
• and
• at least one brake lining disposed between surfaces where the friction is generated, wherein the shaft has mounted thereto a graduation carrier having a measuring graduation of a position-measuring device comprising:
• a scanner mounted to the armature plate and configured to generate scanning signals by scanning the measuring graduation;
• evaluation electronics configured to process the scanning signals into a digital angle value of the shaft;
• and
• an interface configured to communicate with subsequent electronics,
• wherein the scanning signals are dependent on a position of the armature plate in the axial direction of the shaft, and wherein a measure of the position of the armature plate in the axial direction of the shaft is determinable from the scanning signals by the evaluation electronics.