Live center viscous clutch

A viscous clutch assembly comprising:

• a rotor;
• a housing that at least partially surrounds the rotor;
• a center shaft rotationally fixed to the housing;
• a mounting disk rotationally fixed to the rotor, wherein at least a portion of the mounting disk extends outside the housing;
• a hub rotationally fixed to both the rotor and the mounting disk;
• a bearing set rotatably supporting the hub on the center shaft;
• a working chamber defined between the rotor and the housing;
• a reservoir for holding a supply of a shear fluid;
• an electromagnetic coil;
• a valve assembly to selectively control flow of the shear fluid between the reservoir and the working chamber, the valve assembly including an armature that is selectively movable in response to magnetic flux generated by the electromagnetic coil, wherein the magnetic flux is transmitted between the electromagnetic coil and the armature along a flux circuit, wherein the flux circuit is configured to travel through a magnetic flux-conductive portion of the hub that axially traverses the mounting disk.

A method for use with a viscous clutch, the method comprising:

• delivering a torque input to a center shaft of the viscous clutch, wherein the torque input rotates a housing affixed to the center shaft;
• energizing an electromagnet to actuate a valve assembly that governs a volume of the shear fluid present in a working chamber within the viscous clutch;
• transmitting magnetic flux between the electromagnet and the valve assembly along a flux circuit;
• transmitting torque to an output rotor as a function of the volume of the shear fluid present in the working chamber;
• rotating a mounting disk rotationally fixed to the output rotor by way of a hub when torque is transmitted to the output rotor, wherein at least a portion of the mounting disk is located outside the housing;
• and
• passing the magnetic flux axially across the mounting disk as the magnetic flux is transmitted along the flux circuit.