Patent ID: 8464847

Claim:
A friction brake for a shaft and a mounting part which are rotatable in relation to one another about a rotational axis and are components of an electrical drive, wherein the friction brake is permanent magnetically excitable, said friction brake comprising: a first brake element having a first friction surface and mechanically connected to the mounting part, said friction surface forming a magnetic pole; a second brake element having a second friction surface and mechanically connected to the shaft, said first and second brake elements being magnetically attracted to one another; and an electromagnetically actuatable activation mechanism applying a force to press the first and second brake elements against one another during a braking process or stopping process in such a way that the first and second friction surfaces bear against one another and contact in a region of a contact surface, with a magnetic flux flowing through said contact surface, wherein the first and second friction surfaces are formed by axially protruding webs and are configured in such a way that the contact surface engages with only a part of each of the first and second friction surfaces at any point in time during a braking process or stopping process, and a relative position of the contact surface with respect to each of the first and second friction surfaces changes during a braking process.