Abstract

A recliner mechanism particularly adapted for motor vehicle seats is described. In accordance with this invention, the adjusted position of the seat back is controlled by using a recliner mechanism which includes a coil spring clutch which is selectively tightened or loosened around an actuator clutch drum. The upper recliner structure has a toothed quadrant which meshes with a recliner gear which rotates the rotating actuator clutch drum. A lever is employed to cause relative rotation between a pair of actuator cam plates which are connected to extending ends of a coil clutch spring. Movement of the actuator lever selectively causes the coil clutch spring to tighten or loosen around the actuator clutch drum. In accordance with another feature of this invention, a redundant positioning pawl is provided which prevents unrestrained motion of the upper recliner structure in the event of a failure or improper operation of the coil spring clutch actuator. The tendency of the recliner to "creep" when subjected to shock loading and vibration is eliminated by the use of a spring which biases the cam plates to the engaged position.