Patent ID: 7588131

Claim:
A magnetorheological clutch comprising a stationary part, a primary part having primary disks and a secondary part having secondary disks wherein at least one of the primary part and the secondary part coaxially rotates relative to the respective other part, with a space containing a magnetorheological fluid being formed between the primary part and the secondary part in which the primary disks and the secondary disks alternate sequentially in the direction of the common axis and with a regulatable magnetic field acting on the magnetorheological fluid, the magnetorheological clutch further comprising: a) at least one magnetic coil having a first yoke arranged in the space containing the magnetorheological fluid such that the primary disks and the secondary disks are located at both sides of the first yoke; b) end surfaces of the first yoke at both sides parallel to the primary disks and to the secondary disks from which the magnetic field lines exit or into which they enter substantially at right angles and comprises parts of opposite poles separated from one another by zones of low magnetic permeability; c) second yokes, each having an end face parallel to the disks, located adjacent to the outermost disks in the axial direction.