Lifter assembly for a powered fastener driver

A powered fastener driver comprising:

• a driver blade movable from a top-dead-center (TDC) position toward a driven or bottom-dead-center (BDC) position for driving a fastener into a workpiece, the driver blade defining a driving plane;
• a gas spring mechanism for driving the driver blade toward the BDC position;
• a lifter assembly having a rotary lifter for returning the driver blade from the BDC position toward the TDC position,
• a motor that provides torque to a drive shaft upon which the rotary lifter is coupled for selective co-rotation therewith to return the driver blade from the BDC position toward the TDC position;
• and
• a cam mechanism positioned between the drive shaft and the rotary lifter,
• wherein, during rotation of the rotary lifter and a reaction torque on the rotary lifter exceeds a predetermined torque limit, the cam mechanism moves the rotary lifter along a rotational axis of the rotary lifter from a first position, in which the rotary lifter is in the driving plane, and a second position, in which the rotary lifter is out of the driving plane.