Clutch with magneto-rheological operator for transfer cases and the like

A clutch for disposition in a power transmission system comprising, in combination,

• an input member,
• an output member,
• a clutch assembly for selectively transferring torque between said input member and said output member,
• a clutch operator assembly including a pair of adjacent plates, one of said plates connected to said input member for rotation therewith, each of said plates having a face defining a plurality of recesses arranged in opposed relationship, a like plurality of load transferring members disposed in said recesses, a electromagnetic coil, a rotor coupled to an other of said plates for rotation therewith, said rotor having a circular plate and a pair of spaced apart annuli extending from said circular plate, said pair of annuli at least partially surrounding said electromagnetic coil, an armature adjacent said rotor and connected to said output member for rotation therewith,
• a magneto-rheological assembly operably disposed between said rotor and said armature and adjacent said electromagnetic coil, one of said rotor and said armature defining an annular chamber and the other of said rotor and said armature defining an annular member projecting into said chamber, a magneto-rheological fluid disposed in said annular chamber and seals for maintaining said magneto-rheological fluid in said annular chamber, whereby magnetic flux generated by said electromagnetic coil increases the viscosity of said magneto-rheological fluid.

A clutch for disposition in the drive line of a power transmission system comprising, in combination,

• an input member,
• an output member,
• a clutch assembly for selectively coupling said input member and said output member, and
• a clutch operator assembly including a pair of adjacent members defining cam surfaces and cooperating cam devices for separating said adjacent members upon relative rotation, one of said adjacent members disposed for rotation with said input member, an electromagnetic coil, a rotor assembly disposed for rotation with an other of said adjacent members, said rotor having a circular plate defining first and second opposed faces, a singular annulus extending in one direction from one of said faces of said circular plate and a pair of spaced apart annuli extending in an opposite direction from the other of said faces of said circular plate, said pair of annuli at least partially surrounding said electromagnetic coil, an armature assembly disposed adjacent said rotor assembly and connected to said output member for rotation therewith, said armature assembly including an annular chamber for receiving said single annulus of said rotor assembly, seals disposed between said armature assembly and said rotor assembly and a magneto-rheological fluid disposed in said annular chamber, whereby activation of said electromagnetic coil generates magnetic flux in said magneto-rheological fluid, increasing its viscosity, causing drag between said armature assembly and said rotor assembly and engaging said clutch assembly.

A transfer case for providing torque to a primary drive line and a secondary drive line of a motor vehicle comprising, in combination,

• an input member coupled to a primary drive line,
• an output member coupled to a secondary drive line,
• a clutch assembly for selectively transferring torque between said input member and said output member,
• a clutch operator assembly including a pair of adjacent members defining cam surfaces and cooperating cam devices for separating said adjacent members upon relative rotation, one of said adjacent members disposed for rotation with said input member, an electromagnetic coil, a rotor assembly disposed for rotation with an other of said adjacent members, said rotor having a circular plate and a pair of spaced apart annuli extending from said circular plate, said pair of annuli at least partially surrounding said electromagnetic coil, an armature assembly adjacent said rotor assembly and connected to said output member for rotation therewith,
• a magneto-rheological assembly operably disposed between said rotor and said armature and operably adjacent said electromagnetic coil, one of said rotor and said armature defining an annular chamber and the other of said rotor and said armature defining an annular member projecting into said chamber, a magneto-rheological fluid disposed in said annular chamber and seals for maintaining said magneto-rheological fluid in said annular chamber.