Patent ID: 8205727

Claim:
Electromagnetic brake ( 1 ) for an electric drive, comprising at least one brake body ( 3 ), which has at least one permanent magnet ( 4 ), at least one electromagnet ( 5 ) with an electromagnetic exciting coil ( 6 ), an external pole formed as an external ring ( 7 ), and an internal pole formed as an internal ring ( 8 ), wherein the brake body ( 3 ) is locked in rotation with a stator of the electric drive, and also with an armature disc ( 12 ), which is locked in rotation with a rotatable shaft of the drive, wherein the armature disc ( 12 ) forms a magnetic circuit with the external pole and with the internal pole, and also with the permanent magnet ( 4 ) via an air gap, and wherein the armature disc ( 12 ) is drawn against the brake body ( 3 ) in a first position by a magnetic force of the permanent magnet ( 4 ) which overcomes a force of a spring ( 16 ), and for the exciting coil ( 6 ) in an energized state, the electromagnet ( 5 ) compensates, the magnetic field of the permanent magnet ( 4 ) at least to the extent that the armature disc ( 12 ) is lifted to a second position away from the brake body ( 3 ) by the spring force a radial cross-sectional dimension or cross-sectional thickness (d) of the permanent magnet ( 4 ) generating the braking force between an internal diameter and an external diameter thereof is smaller than an axial dimension thereof, the permanent magnet ( 4 ) is arranged in an axial direction between the armature disc ( 12 ) and the exciting coil ( 6 ).