Abstract: A hydrodynamic coupling apparatus (10) for transmitting torque between driving and driven elements includes an input shaft (14), a first end (16) of which is rotatably supported in a case (12) and a second end (18) of which is connectable to a torque generator (20). A hydrodynamic clutch (22) is connected to the first end (16) of the input shaft (14) and includes an impeller (34) and a turbine (36) enclosed in a clutch housing (24). The impeller (34) is fixed to the first end (16) of the input shaft (14), and the turbine (36) is rotatably supported adjacent the impeller (34). Both the impeller (34) and the turbine (36) are immersed in magnetorheological fluid (30). An electromagnetic field generator (32) is supported adjacent the clutch housing (24) and is operable to generate a magnetic field in the magnetorheological fluid (30). The field generator is adjustable to adjust the density of the magnetic field flux and, consequently, the amount of torque transferred from the impeller (34) to the turbine (36).

Abstract: A transfer case for a vehicle having two-wheel drive and four-wheel drive operating modes operatively established by a drive transfer mechanism that is selectively employed to interconnect a main power drive shaft construction for the drive of a first set of wheels with an auxiliary drive shaft for the drive of a second set of wheels. The drive transfer mechanism includes a clutch assembly package comprising a control rod supported for movement in a direction coaxial to the longitudinal axis of the auxiliary drive shaft. The clutch assembly includes a clutch collar supported within the auxiliary drive shaft on the control rod for movement therewith to alternately connect and disconnect the power shaft with the auxiliary drive shaft. For multi-ratio case operation, the power shaft construction may have an input and output power shaft sections that are selectively interconnected by a planetary gear set and a speed shift collar.

Abstract: A transfer case for a vehicle having two-wheel drive and four-wheel drive operating modes operatively established by a drive transfer mechanism that is selectively employed to interconnect a main power drive shaft construction for the drive of a first set of wheels with an auxiliary drive shaft for the drive of a second set of wheels. The drive transfer mechanism includes a clutch assembly package comprising a control rod supported for movement in a direction coaxial to the longitudinal axis of the auxiliary drive shaft. The clutch assembly includes a clutch collar supported within the auxiliary drive shaft on the control rod for movement therewith to alternately connect and disconnect the power shaft with the auxiliary drive shaft. For multi-ratio case operation, the power shaft construction may have an input and output power shaft sections that are selectively interconnected by a planetary gear set and a speed shift collar.