Abstract: The boxes are stacked in a station from which they are collected singly by suitable devices and transferred to a conveyor which carries them to the feed store of the box-filling machine, where they are released singly at a frequency such that the load level of the store remains within values which permit reliable operation of the devices which extract the boxes from the bottom of the store and insert them into the box-filling machine. The conveyor comprises equally spaced grippers consisting of strip springs bent longitudinally in the form of a bow and positioned with the concave part facing the belt of the conveyor to which they are fixed by their intermediate part with a clearance, both rounded ends of the strips normally being in contact with the belt. In the phase of collection and release of the boxes, the strips travel around small diameter pulleys, so that the bending of the strips decreases, facilitating the insertion of the boxes between the strips and the belt and their extraction therefrom.