Abstract: A conveyor for transporting articles includes an upper surface for transporting the articles and a top guide that is resiliently supported relative to the upper surface for preventing the articles from tipping over as they are transported. A plurality of resilient supporting mechanisms, such as gas springs, is provided on each of the opposite sides of the conveyor. A mechanism is provided to selectively move the top guide toward the upper surface of the conveyor against the urging of the gas springs to position the top guide at a predetermined distance relative to the upper surface of the conveyor. The mechanism includes a plurality of flexible cables having first ends that are connected to the top guide and second ends that are connected to a pair of actuating members that are supported on the conveyor for sliding movement.