SPIRAL CAM CLUTCH ACTUATION SYSTEM FOR TWO-SPEED TRANSFER CASE

摘要

A transfer case includes a two-speed range unit, a friction clutch, an actuation mechanism and a control system. The actuation mechanism includes an electric motor, a geartrain driven by the motor, a range actuator assembly and a mode actuator assembly. The range actuator assembly includes a driveshaft driven by the geartrain, a cam driven by the driveshaft and a shift fork having a follower retained in a groove formed in the cam and a fork engaging a shift collar associated with the range unit. The mode actuator assembly has a face cam with spiral cam surfaces and a control gear with radially-moveable rollers engaging the cam surfaces. The control gear is rotatively driven by the geartrain. The face cam is axially moveable for controlling engagement of the friction clutch. An anti-rotation mechanism limits rotation of the face cam in response to continued rotation of the control gear.