Abstract: A conveyor with a plurality of article supporting stations has a reciprocatable shuttle mechanism equipped with dogs which engage and advance articles one station on each advance stroke of the shuttle. All dogs are set in article engaging position at the end of each return stroke of the shuttle. A series of accumulating stations extends from the unloading toward the loading end of the conveyor, and accumulating mechanism actuatable independently of the shuttle is operable to reset the dogs of each of these stations to non-engaging position in response to the presence of articles. A control system normally operates the conveyor on a simple cycle of successive advance and return strokes of the shuttle until, with articles detected at the last two stations, the accumulating mechanism is cycled prior to a shuttle advance stroke.