Patent attributes
An electromagnetic friction clutch has at least two clutch parts that are mounted so as to be rotatable relative to each other and movable toward and away from each other and that touch each other with a contact force in the position of use. The clutch parts are located in a magnetic circuit, which is guided in the clutch parts in a soft magnetic material in sheet form. Positioned in the magnetic circuit is an electromagnet having a soft magnetic core and a coil. The magnetic circuit has air gaps between the soft magnetic core and at least one of the clutch parts. The flux density in the magnetic circuit, and thus the contact force, is modifiable via the current applied to the coil. The magnetic flux changes at least ten flux crossover points one after the other in the direction of flow between the clutch parts. The cross section of the magnetic flux in at least one air gap is at least five times greater than the smallest flux cross section in the soft magnetic material.