BorgWarner Inc.
Transfer case with range and mode actuator having cam follower mechanism to overcome blocked shift events and sensor configuration permitting detection of fork positions

Abstract:

A transfer case with an actuator for operating a two-speed transmission (i.e., range mechanism) and a clutch (i.e., mode mechanism). The actuator employs a motor-driven cam structure that coordinates the movement of a first fork, which is associated with the range mechanism, and a second fork that is associated with the mode mechanism. A resilient coupling is employed to provide compliance between the motor and the cam structure in the event that tooth-on-tooth contact inhibits the range mechanism from changing from a high-range mode and a low range mode. Compliance is provided between the cam structure and the second fork in the event that tooth-on-tooth contact inhibits the mode mechanism from changing from a 2WD mode to a 4WD mode. A sensor system identifies the placement of the first and second forks in various positions and responsively generates associated sensor signals.