Abstract: There is provided for use with a conveyor, an unloading apparatus for automatically removing a stack of sheets from a succession of shelves or bins, as in a collator, and conveying it to a desired location. The unloading apparatus includes a gripper which is adapted to advance to grip the sheets as presented on a shelf and then retract to insert the stack of sheets onto a conveyor, e.g. a tape conveyor. The gripper includes a four-bar linkage whereby the upper one of its jaws is elevated from a position beneath the plane of travel of the stack of sheets into gripping relation with the stack by a spring biased over-center action. The gripper with the stack is moved linearly onto the conveyor which takes over from the gripper to continue the movement of the stack of sheets. At the delivery end of the gripper stroke, the four-bar linkage is actuated in an opposite direction, the stack released, and the upper jaw retracted out of the path of the stack.