Hinge assembly for tonneau cover

摘要

A hard tonneau cover is pivotally attached to each side wall of a truck cargo box having a tail gate by a hinge assembly. Each hinge assembly includes a four bar linkage and a drive mechanism. The four bar linkage consists of a tonneau bracket that is secured to the tonneau cover, a mounting bracket, a hinge link that is pivotally attached to the tonneau bracket at one end by a first pivot and to the mounting bracket at an opposite end by a second pivot, and a control link that is pivotally attached to the tonneau bracket at one end by a third pivot and to the mounting bracket at an opposite end by a fourth pivot. The drive mechanism has a pivot arm that is pivotally attached to the mounting bracket by a fifth pivot, and a drive arm that is pivotally attached to the pivot arm by a sixth pivot and pivotally attached to the tonneau bracket by a seventh pivot so that the tonneau cover and bracket are moved between a closed position and an open position by rotation of the pivot arm. A gas spring that is attached to the mounting bracket and to the pivot arm biases the tonneau cover and tonneau bracket to the closed position. The tonneau cover is opened and closed by an electric motor and an electromagnetic clutch that are supported by the mounting bracket. The electromagnetic clutch has an input member that is driven by the electric motor and an output member that drives a pinion gear. The pinion gear in turn drives a sector gear that is attached to the pivot arm.